BIOLOGY
By: Raul Ramos
2014-2015 EDITION
Florida EOC Test Study Guide
Pg. 1
About the Author
Educate
This study guide is dedicated to my students, past, present, and
future. I can only hope that I have or will make a difference in your
lives. I also dedicate this study guide to my biology colleagues from
Mater Lakes, Mr. Lima and Ms. Abreu. They both have been
excellent instructors and mentors for our future generation.
“Education is the most powerful weapon which you can use to
change the world.”
-Nelson Mandela
“If I have seen further it is by standing on the shoulders of
Giants.”
-Isaac Newton
“The scientific man does not aim at an immediate result. He does
not expect that his advanced ideas will be readily taken up. His
work is like that of the planter - for the future. His duty is to lay
the foundation for those who are to come, and point the way.”
-Nikola Tesla
Raul Ramos grew up in
Miami, Florida where he
attended public, private,
and charter Elementary,
Middle, and High School,
respectively.
He graduated Cum Laude
from Mater Academy
High School in 2008 and
attended Miami Dade
Honors College, North
Campus. He graduated
from MDC in 2010 with
Highest Honors and
Distinction, earning an
Associate in Arts degree
in Biology.
In 2012, Raul graduated
from Florida International
University with a Bachelor
of Science degree in
Biological Science and a
minor in chemistry.
Since 2012, Raul has been
teaching Biology and
Health at Mater Lakes
Academy. He won the
rookie teacher of the year
award in 2014.
Raul is happily married
and aspires to become a
doctor of optometry in
the near future.
Pg. 2
I, Raul Ramos, do not, in any way or form, take credit for the pictures that are used throughout this study guide. The pictures on this
study guide are not my work. I am using them for educational purposes to better educate our students in the biology.
This study guide is free of charge and will not be sold for any profit.
What is fair use?
The Copyright Act gives copyright holders the exclusive right to reproduce works for a limited time period. Fair use is a limitation on this
right. Fair use allows people other than the copyright owner to copy part or, in some circumstances, all of a copyrighted work, even
where the copyright holder has not given permission or objects.
How does fair use fit with copyright law?
Copyright law embodies a bargain. It gives copyright holders a set of exclusive rights for a limited time period as an incentive to create
works that ultimately enrich society as a whole. In exchange for this limited monopoly, creators enrich society by, hopefully, contributing
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However, copyright law does not give copyright holders complete control of their works. Copyrighted works move into "the public
domain" and are available for unlimited use by the public when the copyright term expires (see Public Domain FAQ). But even before
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By carving out a space for creative uses of music, literature, movies, and so on, even while the works are protected by copyright, fair use
helps to reduce a tension between copyright law and the First Amendment's guarantee of freedom of expression. The Supreme Court has
described fair use as "the guarantee of breathing space for new expression within the confines of Copyright law."1
How does the court know if a use is fair?
Whether a use is fair will depend on the specific facts of the use. Note that attribution has little to do with fair use; unlike plagiarism,
copyright infringement (or non-infringement) doesn't depend on whether you give credit to the source from which you copied. Fair use
is decided by courts on a case-by-case basis after balancing the four factors listed in section 107 of the Copyright Act. Those factors are:
1.


2.
3.
4.
The purpose and character of the use of copyrighted work
Transformative quality - Is the new work the same as the copyrighted work, or have you transformed the original work, using it in a
new and different way?
Commercial or noncommercial - Will you make money from the new work, or is it intended for nonprofit, educational, or personal
purposes? Commercial uses can still be fair uses, but courts are more likely to find fair use where the use is for noncommercial
purposes.
The nature of the copyrighted work
A particular use is more likely to be considered fair when the copied work is factual rather than creative.
The amount and substantiality of the portion used in relation to the copyrighted work as a whole
How much of the copyrighted work did you use in the new work? Copying nearly all of the original work, or copying its "heart," may
weigh against fair use. But "how much is too much" depends on the purpose of the second use. Parodies, for example, may need to
make extensive use of an original work to get the point across.2
The effect of the use upon the potential market for or value of the copyrighted work
This factor applies even if the original is given away for free. If you use the copied work in a way that substitutes for the original in
the market, that will weigh against fair use. Uses of copyrighted material that serve a different audience or purpose are more likely
to be considered fair.
These factors are guidelines, and they are not exclusive. As a general matter, courts are often interested in whether or not the individual
making use of a work has acted in good faith.
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Table of Contents
About the Author Educate ......................................................................................................................... 1
What is fair use? ................................................................................................................................... 2
How does fair use fit with copyright law? ........................................................................................... 2
How does the court know if a use is fair? ........................................................................................... 2
Ecology .......................................................................................................................................................... 8
General Ecology ........................................................................................................................................ 8
Energy Transfer ..................................................................................................................................... 8
Producers .............................................................................................................................................. 9
Consumers ............................................................................................................................................ 9
Photosynthesis and Cellular Respiration .............................................................................................. 9
Symbiotic Relationships ...................................................................................................................... 10
Succession ........................................................................................................................................... 10
Biotic and Abiotic Factors ................................................................................................................... 10
Population Ecology ................................................................................................................................. 11
Denisty ................................................................................................................................................ 11
Limiting Factors ................................................................................................................................... 11
Environmental Ecology ........................................................................................................................... 11
Environmental Problems..................................................................................................................... 11
Evolution ..................................................................................................................................................... 12
Introduction to Evolution........................................................................................................................ 12
Ideas that Shaped Darwin’s Thinking ...................................................................................................... 13
Philosophical Dilemma with Evolution ................................................................................................... 14
Darwin’s Idea of Natural Selection came from Artificial Selection ......................................................... 15
More on Natural Selection ...................................................................................................................... 15
Evidence for Evolution ............................................................................................................................ 15
Evolution in Genetics Terms ................................................................................................................... 17
Speciation................................................................................................................................................ 19
HIV Evolution .......................................................................................................................................... 20
The Fossil Record .................................................................................................................................... 20
The Origin of Life ......................................................................................................................................... 21
Endosymbiotic Theory ............................................................................................................................ 21
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Miller-Urey Experiment .......................................................................................................................... 22
Classification ............................................................................................................................................... 22
Taxonomy................................................................................................................................................ 22
Phylogeny ................................................................................................................................................ 23
Water .......................................................................................................................................................... 24
Hydrogen and Covalent Bonds................................................................................................................ 24
Properties of Water ................................................................................................................................ 25
pH ............................................................................................................................................................ 27
Biochemistry ............................................................................................................................................... 28
Carbohydrates......................................................................................................................................... 28
Lipids ....................................................................................................................................................... 29
Proteins ................................................................................................................................................... 29
Nucleic Acids ........................................................................................................................................... 30
Cytology ...................................................................................................................................................... 31
Introduction ............................................................................................................................................ 31
Cytoskeleton of the Cell .......................................................................................................................... 32
Animal Cell (a type of Eukaryotic Cell) .................................................................................................... 34
Plant Cell (a type of Eukaryotic Cell) ....................................................................................................... 35
Cell Transport .......................................................................................................................................... 36
Homeostasis ................................................................................................................................................ 40
Negative Feedback .................................................................................................................................. 40
Positive Feedback ................................................................................................................................... 40
The Nervous System ................................................................................................................................... 42
Introduction ............................................................................................................................................ 42
Two Nervous Systems ............................................................................................................................. 42
Brain ........................................................................................................................................................ 42
The Cardiovascular System ......................................................................................................................... 43
Introduction ............................................................................................................................................ 43
Blood Vessels .......................................................................................................................................... 43
Heart ....................................................................................................................................................... 43
Blood Circulation ..................................................................................................................................... 44
Coronary Circulation ............................................................................................................................... 44
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Blood ....................................................................................................................................................... 45
Blood Pressure ........................................................................................................................................ 45
Heart Rate & Blood Pressure Relationship and Disease ......................................................................... 46
The Immune System ................................................................................................................................... 47
Introduction ............................................................................................................................................ 47
Lines of Defense ...................................................................................................................................... 47
The lymphocytes ..................................................................................................................................... 47
Medications to Fight Disease .................................................................................................................. 48
Types of Immunity .................................................................................................................................. 48
Vaccines .................................................................................................................................................. 49
Viruses ..................................................................................................................................................... 50
Viral Life Cycles ....................................................................................................................................... 50
HIV and AIDS ........................................................................................................................................... 50
Botany ......................................................................................................................................................... 52
Plant Evolution ........................................................................................................................................ 52
Bryophytes .......................................................................................................................................... 52
Tracheophytes..................................................................................................................................... 53
Flower Anatomy .................................................................................................................................. 53
Angiosperm Classification: Monocots and Dicots................................................................................... 54
Plant Characteristics, Structure & Function ............................................................................................ 55
The Leaf ............................................................................................................................................... 55
Plant Tissues........................................................................................................................................ 56
Life Cycle of Plants .................................................................................................................................. 57
Enzymes ...................................................................................................................................................... 58
Enzyme Naming ...................................................................................................................................... 59
Factors Affecting Reaction Rates ............................................................................................................ 59
Energy ......................................................................................................................................................... 61
Introduction ............................................................................................................................................ 61
ATP .......................................................................................................................................................... 61
Photosynthesis ............................................................................................................................................ 62
Introduction ............................................................................................................................................ 62
PS II...................................................................................................................................................... 63
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PS I ....................................................................................................................................................... 64
The Calvin cycle: C3 Pathway................................................................................................................... 65
Photorespiration ..................................................................................................................................... 65
C4 Pathway .............................................................................................................................................. 66
Crassulacean Acid Metabolism (CAM) Photosynthesis .......................................................................... 66
Cellular Respiration ..................................................................................................................................... 67
Introduction ............................................................................................................................................ 67
Aerobic Respiration (with oxygen).......................................................................................................... 68
Anaerobic Respiration (without oxygen) ................................................................................................ 69
Comparing photosynthesis and cellular respiration ................................................................................... 70
Cell Growth ................................................................................................................................................. 71
Check-Points ........................................................................................................................................... 71
Cancer Treatment ................................................................................................................................... 72
Mitosis......................................................................................................................................................... 73
Binary Fission vs. Mitosis ............................................................................................................................ 75
Meiosis ........................................................................................................................................................ 75
Meiosis .................................................................................................................................................... 76
Meiosis II ................................................................................................................................................. 77
Mitosis vs. Meiosis ...................................................................................................................................... 78
Comparison Graph .................................................................................................................................. 78
Human Karyotype ....................................................................................................................................... 79
Reproductive Systems................................................................................................................................. 79
Purpose of Reproduction ........................................................................................................................ 79
Male Reproductive System ..................................................................................................................... 80
Female Reproductive System.................................................................................................................. 80
Introduction to DNA and RNA ..................................................................................................................... 81
DNA History............................................................................................................................................. 83
DNA Replication .......................................................................................................................................... 83
The Process of DNA Replication .............................................................................................................. 84
Mutations in DNA........................................................................................................................................ 86
Protein Synthesis ........................................................................................................................................ 88
Introduction to Protein Synthesis ........................................................................................................... 88
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Transcription ........................................................................................................................................... 88
Translation .............................................................................................................................................. 89
Mendelian Genetics .................................................................................................................................... 90
Introduction to Heredity ......................................................................................................................... 90
Mendel’s Laws......................................................................................................................................... 91
The Punnett Square (Monohybrid Cross) ............................................................................................... 92
Genotype vs. Phenotype ......................................................................................................................... 93
Homozygous and Heterozygous Genotypes ........................................................................................... 94
Test Cross ................................................................................................................................................ 95
Single-Gene Traits and Polygenic-geneTraits.......................................................................................... 96
Beyond Mendelian Genetics: Incomplete Dominance, Codominance, & Sex-Linked Traits .................. 97
Sex-Linked Traits ..................................................................................................................................... 98
Pedigrees..................................................................................................................................................... 99
Autosomal Dominant Trait Characteristics ............................................................................................. 99
Autosomal Recessive Trait Characteristics: ............................................................................................ 99
X-Linked Recessive Trait Characteristics ............................................................................................... 100
X-Linked Dominant Trait Characteristics............................................................................................... 100
Y-Linked Trait Characteristics................................................................................................................ 100
Biotechnology ........................................................................................................................................... 101
Gel electrophoresis .............................................................................................................................. 101
Recombinant DNA................................................................................................................................. 102
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Ecology
SC.912.E.7.1
Analyze the movement of matter and energy through the different biogeochemical cycles, including water and
carbon.
SC.912.L.17.4
Describe changes in ecosystems resulting from seasonal variations, climate change, and succession.
SC.912.L.17.5
Analyze how population size is determined by births, deaths, immigration, emigration, and limiting factors (biotic
and abiotic) that determine carrying capacity.
SC.912.L.17.8
Recognize the consequences of the losses of biodiversity due to catastrophic events, climate changes, human
activity, and the introduction of invasive, non-native species
SC.912.L.17.9
Use a food web to identify and distinguish producers, consumers, and decomposers. Explain the pathway of energy
transfer through trophic levels and the reduction of available energy at successive trophic levels.
SC.912.L.17.20
Predict the impact of individuals on environmental systems and examine how human lifestyles affect sustainability.
.SC.912.L.18.9
Explain the interrelated nature of photosynthesis and cellular respiration.
General Ecology
Energy Transfer
The sun is our planets main source of energy. The sun provides food to producers like plants, and the
sun powers the biogeochemical cycles, such as the water cycle.
Energy is transferred from the prey to the predator: grass  cow
(This type of predation with a producer is called herbivory)
The arrow represents where the energy is transferred to
There is more biomass and energy at the bottom of a pyramid than at the top.
The first organism in a food chain, is the same as the “bottom of the pyramid”
grass  cow  lion (the grass has the greatest biomass & energy)
10% of the energy is passed from the bottom trophic level to the level right above it.
90% of the energy is lost as heat to the environment. (This is why you need to talk less in class…because
then it gets hot)
1st Law of Thermodynamics states that ENERGY cannot be created or destroyed. Energy is transferred
(examples: solar energy  chemical energy  mechanical energy)
Law of conservation of matter states that MATTER cannot be created or destroyed. Unlike energy, which
flows in one direction, matter cycles. We call it the biogeochemical cycle: water cycle, carbon cycle,
nitrogen cycle.
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Phytoplankton is “plant-like” plankton (it is a producer)
Zooplankton is “animal-like” plankton (it is a type of consumer)
Decomposers break down organic matter through a process of absorption.
Fungi and Bacteria are decomposers.
Producers and consumers will all eventually be decomposed
Producers
Plants, Algae, and bacteria are producers. They can “produce” their own food through sunlight or
chemicals.
Plants, Algae, and Cyanobacteria convert the sunlight into energy. This process is called photosynthesis.
Producers, such as plants, algae, and bacteria are also known as autotrophs.
Because plants, algae, and cyanobacteria use the energy from the sun, they are specifically called
photoautotrophs.
The rest of the bacteria use chemicals to produce their own food. They are then called
chemoautotrophs.
Remember that Fungi are not plants! Fungi are not producers! They do not perform photosynthesis.
Consumers
A consumer is an organism that cannot make its own food; it needs to feed off of other organisms to
obtain energy. Another word for consumer is heterotroph.
A herbivore is a consumer that eats plants (example: cow)
A carnivore is a consumer that eats meat (example: lion)
An omnivore is a consumer that eats plants and meat (example: humans)
A decomposer absorbs decaying matter (example: fungi and bacteria)
A detritivore actually eats dead matter (example: worms)
Photosynthesis and Cellular Respiration
Photosynthesis (to make/synthesize food with light) is a process used by producers, such as plants to
make their own food.
Plants absorb the carbon dioxide in the atmosphere (which causes global warming) and release oxygen
in the process.
If plants do not capture the carbon dioxide, excess heat is trapped in the Earth, and the Earth gets
hotter. Then the ice caps melt, the sea level rises, and we all DIE….
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(because carbon dioxide is a greenhouse gas, and the greenhouse effect causes HEAT)
Photosynthesis Equation (what do we give them / what do they give us):
6CO2 + 6H2O + Sunlight  C6H12O6 + 6O2 (FYI: C6H12O6 is the sugar glucose)
The opposite of photosynthesis is cellular respiration. Who does cellular respiration? Hmmm…All living
things because they all have CELLS. So, yes, plants also do cellular respiration in addition to
photosynthesis.
Cellular Respiration Equation:
C6H12O6 + 6O2  6CO2 + 6H2O + ATP
(FYI: ATP is a high energy molecule)
Symbiotic Relationships
Mutualism: both organisms benefit from their relationship (+/+)
(example: bumble bee helps pollinate the flower, and the flower provides food for the bee)
Commensalism: one organism benefits, but the other organism neither benefits nor is harmed (+/0)
(example: a small fish swims next to a shark for protection from other fish, but the fish does not provide
anything in return to the shark) “Wouldn’t you like to have a big brother by your side to protect you
from bullies?”
Parasitism: one organism benefits while harming the other organism, called its host (+/-)
(example: A tapeworm in your intestines will eat all your food. Eventually you begin to get skinny and
notice something is wrong)
Succession
A succession is followed by some type of disturbance in nature.
Primary succession begins with bare rock and eventually forms into a forest. Lichens are the pioneer
species in primary succession. They can survive in these extreme conditions…Would you eat rock?
Lichens will.
Hawaii was probably a result of primary succession. Lava from volcano cools and becomes rock.
Eventually the rock becomes soil and is fertilized over hundreds of years.
Secondary succession results when a previous environment with SOIL has been partially or completely
destroyed. Secondary succession occurs quicker than primary. The Florida Everglades are constantly
being burned down and re-grow. The Everglades experience secondary succession.
Biotic and Abiotic Factors
A biotic factor is a living factor within an ecosystem (example: plants, birds, trees)
An abiotic factor is a nonliving factor within an ecosystem (example: soil, sunlight, water, wind)
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Population Ecology
Denisty
Population Density is defined as the number of individuals per area.
Group A: 5 individuals in an area of 50 square feet
Group B: 30 individuals in an area of 50 square feet
Which group (A or B) has the greatest density? Group B has the greatest density because it has more
individuals than A, which has the same area.
Group C: 5 individuals in an area of 50 square feet
Group D: 20 individuals in an area of 500 square feet
Which group (C or D) has the greatest density? Group C has the greatest density of 0.1 (5 individuals
divided by 50 square feet) compared to group D with a density of 0.04 (20 individuals divided by 100
square feet)
Limiting Factors
A density-dependent limiting factor is something that “LIMITS” the population from growing based on
the density of that population. (examples: competition, predation, parasitism and diseases)
The more people in Miami, the less jobs. Jobs are examples of density-dependent limiting factors.
A density-independent limiting factor is something that “LIMITS” the population from growing but does
not depend on the density of that population. (examples: tornadoes, hurricanes, lightning storms,
earthquakes). A tornado doesn’t care how big or small a population is. A tornado will destroy anything in
its way.
Population growth depends on four factors: birth rate, death rate, immigration, and emmigration.
Populations grow exponentially at first but eventually reach a carrying capacity. Once the carrying
capacity for that population is met, the growth becomes “S-shapes” (logistic growth)
Environmental Ecology
Environmental Problems
Chlorofluorocarbons (CFCs) are chemicals that were once in aerosol products. They have caused a huge
hole in our ozone layer. (Please do not confuse CFCs with carbon dioxide. CO2 is a greenhouse gas)
Carbon dioxide is a greenhouse gas. Greenhouse gases cause global warming (hot, hot, caliente)
Acid rain is literally acid in the rain. It destroys statues, forests, etc…
Acid rain forms when nitrogen and sulfur gases mix with water vapor to form nitric acid rain and sulfuric
acid rain. Factories and pollution are responsible for acid rain.
pH is a scale used to determine whether something is acidic or basic. Less than 7 is acidic and greater
than 7 is basic. So what is 7? Water. Acid rain has a pH way below 7. Probably a pH of 3 or 4.
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Evolution
SC.912.L.15.1
Explain how the scientific theory of evolution is supported by the fossil record, comparative anatomy, comparative
embryology, biogeography, molecular biology, and observed evolutionary change.
SC.912.L.15.13
Describe the conditions required for natural selection, including: overproduction of offspring, inherited variation,
and the struggle to survive, which result in differential reproductive success.
SC.912.L.15.14
Discuss mechanisms of evolutionary change other than natural selection such as genetic drift and gene flow.
*Note: When you have a doubt, choose natural selection or common ancestor as the answer.
Introduction to Evolution
Charles Darwin and Alfred Russell Wallace are the fathers of evolution (but mainly Darwin).
Biological evolution is a change in the population over time. Populations evolve, not individuals.
Darwin used the term descent with modification to describe evolution. We (the descendents) are
modified versions of our ancestors.
Charles Darwin was a naturalist (someone who studies nature). He went on a 5 year voyage on a big
British ship called the H.M.S. Beagle. On his journey around the world, he noticed that species vary
globally, locally, and over time.
Darwin’s greatest work came from studying the animals in the Galapagos Islands off the coast of
Ecuador. Darwin realized that tortoises on one island had short necks while tortoises on the other island
had long necks.
Darwin realized that these differences in tortoise necks were not coincidences. The tortoises were built
to live and dwell in the environment that they were in. For example, the tortoises with short necks were
on an island with plenty of vegetation on the ground. Meanwhile, the tortoises with long necks were on
an island where there was no vegetation on the ground. These tortoises needed long necks to reach for
food up high.
Species vary locally
Darwin noticed three different types of birds as he travelled the world: the Rhea (found in S. America),
the Ostrich (found in Africa) and the Emu (found in Australia). These birds look almost the same, but if
Pg. 13
you look carefully, they are all different.
Species vary globally
Darwin also noticed that species change over time. This concept was not acceptable back in the day, for
it was thought that all species were created perfect and could not change. Darwin saw these changes in
the fossil record. Take a look the picture of the armadillo shown below and its extinct ancestor the
glyptodont.
Species vary over time
Ideas that Shaped Darwin’s Thinking
Back in the old days people thought the Earth was 5,000 years old. This idea of Earth’s age was
calculated by Archbishop James Usher.
Now, thanks to carbon dating, fossils, and geology we know that the Earth is approximately 4.54 billion
years old.
Darwin did not believe the Earth was only 5,000 years old. He was highly influenced by the works of
Hutton and Lyell, who concluded that the Earth is extremely old, and the processes that changed Earth
in the past are the same processes that operate in the present. Since the Earth may be a lot older, then
Darwin’s theory would make more sense, since it takes a really long time for new organisms to arise.
Jean-Baptiste Lamarck was a French naturalist who highly influenced Charles Darwin. Lamarck was one
of the first persons to say that species change. Lamarck’s ideas, however, were incorrect and thus
ridiculed. His theory was called Inheritance of Acquired Characteristics. This theory involved a concept
called use and disuses. Organism, such as giraffes, that use their necks to reach the leaves of trees will
pass those characteristics to their offspring. The more you use something, the better it becomes, and it
is passed on to the offspring. (Remember: Lamarck was wrong! Individuals do not evolve. Populations
evolve).
Lamarck thought that evolution led to perfection. However, we know that the process of evolution does
NOT make you better or perfect.
Pg. 14
Another man who influenced Darwin was the economist, Thomas Malthus. Malthus said that war,
famine, and disease, would force the human population to reach a carrying capacity during his time.
Malthus, however, was wrong. We are in 2014 and there are about 7.2 billion people on Earth.
Darwin realized that although Malthus’s work did not apply to humans (because of technological
advancements); his work applied more to animals. Populations tend to stabilize and only those fit to
their specific environments will survive. Nature is a dangerous place.
Philosophical Dilemma with Evolution
Back then, philosophers and scientists did not believe in “evolution” because of the following:
‘you cannot get order and complexity from random chaos alone’
Keep in mind that evolution was thought to occur because of random mutations. So how could these
random mutations lead to such beautiful organisms on Earth with their complex structures?
Charles Darwin realized that such order can occur in nature as a result of a process called natural
selection. Natural selection states that nature will select those individuals that are better suited to their
environments. These individuals will survive, reproduce, and pass on their genetic information to their
offspring.
In better terms: natural selection is the process by which random evolutionary changes are selected for
by nature in a consistent, orderly, non-random way.
But how does this work exactly? Notice the picture below with the light and dark moths. Think for a
second, which moth is better? The answer is none because they are both moths. The only difference is
that one is light and the other dark. Natural selection does not select the best organisms. Natural
selection selects those organisms that are better suited to their environments to survive and reproduce.
In the first example with the light tree, natural selection chooses the light moth to live and reproduce in
that environment because of its ability to camouflage. In the second example with the dark tree, natural
selection chooses the dark moth to live and reproduce in that environment because of its ability to
camouflage.
So you see, nature does not have a thinking mind, but it somehow selects the organisms best suited to
their environments to survive and reproduce based on the organisms’ adaptations.
*Natural selection goes side by side with adaptation and survival of the fittest.
Nature selects those variations that are best adapted to the environments in which they are in, leading
to the reproduction of the organisms, which is termed fitness.
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Evolution is like a “car,” and natural selection is like the “engine.” Natural selection drives evolution.
Darwin’s Idea of Natural Selection came from Artificial Selection
Darwin was curious as to what caused these changes in nature, so Darwin studied changes based on
Artificial Selection. In artificial selection, nature provides the variations, and humans select those they
find useful.
Artificial selection is used to create different breeds of dogs, such as the Boxer, Rottweiler, and German
shepherd. Humans choose the traits they like and thus create different breeds for different purposes.
Artificial selection is also used to grow crops. Broccoli, Cauliflower, Kale, Brussel sprouts, and Cabbage
are all just different breeds of a weed found in the English Channel.
More on Natural Selection
Natural selection is based on the idea that
- nature selects who lives or dies
- organisms struggle to exist
- organisms have variations that allow adaptation
- Fitness (survival of the fittest): those organisms that survive will reproduce & pass their adaptations to
the next generation.
Natural selection only acts on inherited traits because these are the only characteristics that parents can
pass on to their offspring.
Natural selection does NOT make organisms “better.”
Evidence for Evolution
The fossil record provides strong evidence to the theory of evolution. We have found the skulls of
human-like ancestors that may show the gradual change in the human species.
Fossil Record
Embryology, or the study of embryos, provides clues as to how all organisms begin life in a very similar
fashion.
4 different Embryos
Comparative anatomy involves comparing the structures of various organisms to determine their
similarities and differences. Notice on the picture below that man, cow, horse, whale, and bird all have
Pg. 16
similar structures but different functions. This must mean that they share a common ancestor.
Homologous Structures: similar structures but different functions
(they share a common ancestor). Ask yourselves “why do whales
and birds have bones similar to the hands of man?” Could it be that
whales, birds, and man all descended from a common ancestor with
hand-like structures?
Vestigial structures are homologous structures that serve no major function or have lost their function
over time. Examples include the human tail-bone, the wisdom teeth, and the appendix. Ask yourselves
“why do we have wisdom teeth if they serve no function and usually don’t fit in our mouth?” Could it be
that our ancestors, the Neanderthals, had bigger mouths as a result of a different diet? Ask yourselves
“why do we have an appendix if it serves no function?” Could it be that the appendix helped us digest
plants in the past?
Biogeography serves as evidence for evolution because we ask ourselves how is it possible for finches
that live so close to each other in neighboring islands in the Galapagos to all be different species of
finch. This may be due to the kinds of food present on each island of the Galapagos. In some islands
there are plenty of hard seeds, so the finches in this island have grown large beaks to break the seed. In
other islands the only food available is nectar found inside of flowers, so these finches need a long
pointy beak to survive.
Molecular Biology
Ultimately, molecular evidence suggests that mutations, or changes in the DNA as a result of error, lead
to variations among species that would add up over generations and result in all the diversity there is on
Earth today. We see molecular evidence for evolution by comparing DNA from different organisms.
Chimpanzees and humans for example have almost the same DNA.
Notice how the chimpanzee has 0 differences in amino acids when
compared to humans. Thus, the chimp is our closest relative, at least
when it comes to cytochrome c.
Pg. 17
Analogous structures are structures that have a similar function but a different structure.
*Note: Analogous structures do not indicate a recent common ancestor.
Evolution in Genetics Terms
In genetics terms, evolution is the change in allele frequency in a population over time.
An allele is a variation of a gene, and a gene is a piece of a chromosome that codes for information.
There are many genes (eye color gene, rolling tongue gene, widow’s peak gene, etc). The eye color gene
may have variations, such as green eyes, brown eyes, blue eyes, etc. These variations in a gene are
called alleles.
If the population is 80% white and 20% black (allele frequency), and in a few years the alleles become
different (let’s say 40 % white and 60% black), then the population has evolved. The allele frequencies
have changed in the population over time.
All the genes in a population make up the population’s gene pool.
What causes genetic variations for natural selection to act on individuals?
1. Mutations, which are changes in the DNA as a result of a mistake, introduce new
variations.
2. Genetic recombination during sexual reproduction occurs when the DNA from
mommy and daddy combine and shuffle to produce many variations that result in
differences between you and your siblings. This recombination of genes occurs during
sexual reproduction (when mom and dad decide to make a baby).
3. Lateral gene transfer introduces new genes into the new population. This
occurs when on organism, such as a bacterium, transfers its special DNA into
another bacterium. When bacteria have “sex” and transfer information from
one bacterium to the other, this is called conjugation.
Pg. 18
Natural selection acts upon phenotypes, not genotypes. A genotype is the genetic information of an
organism (BB, Bb, bb). The phenotype is the physical expression of a genotype (BB = brown eyes, Bb =
brown eyes, bb = blue eyes).
Some traits, such as the widow’s peak or butt chin are single-gene traits. This means that the trait is
controlled by one gene. Therefore, you either have the trait or not.
Polygenic traits are controlled by more than one gene. Therefore, polygenic traits will have a range of
variations. Skin color, weight, and height are examples of polygenic traits. Evolution may drive polygenic
traits into various modes: stabilizing selection, directional selection, or disruptive selection.
In stabilizing selection, the majority of the population
will exhibit the trait that is in the middle of the bell
curve distribution.
In directional selection, the majority of the population
will shift to the right or left to exhibit one of the two
extreme forms of the trait in the bell curve
distribution.
In disruptive selection, the majority of the population
will sway away from the center of the bell curve and
exhibit traits in either extreme of the bell curve
distribution.
Genetic drift may cause populations to evolve by accident. Genetic drift affects small populations.
Notice the picture below – the man did not intentionally mean to step on the beetles, but he
“accidentally” stepped on a portion of the population of beetles that were green. The population drifted
towards brown.
The bottleneck effect is a type of genetic drift that occurs in a
population when there is a natural disaster and only a few members of
the population survive.
Pg. 19
The founder effect is another example of genetic drift. The founder effect
occurs when small populations of individuals settle in a place, such as an
island or country that is rather uninhabited. This small population of
founders may carry bad genes that can spread to future generations,
harming the population.
Hardy and Weinberg indirectly proved that allele frequency in populations change, thus evolution takes
place. They stated that 5 factors need to occur in order for a population not to evolve. When these 5
factors are present, the population does not evolve and is said to be in Hardy-Weinberg Equilibrium.
A population will NOT evolve if the following 5 principles are met:
1. Random mating
2. Extremely large population
3. No mutations
4. No natural selection
5. No gene flow (no immigration or emigration)
However, we do not mate randomly, our population is not infinitely large, there are mutations, natural
selection does take place, and gene flow is seen when individuals leave and enter countries. Therefore,
because these 5 principles are NOT met, then the population is NOT in Hardy-Weinberg Equilibrium and
is therefore evolving.
The Hardy-Weinberg Principle was expressed mathematically as p + q = 1 and p2 +2pq +q2 =1
(You don’t need to solve any math for the EOC exam)
Speciation
How do you know that a dog and a cat are different species? We use the definition below for biological
species concept to address this question.
Biological species concept:
1. The two species must be able to produce an offspring
2. If an offspring is produced, the offspring must be fertile (this means that it must be able to reproduce)
The horse and the donkey are different species, but they can produce a mule! (Don’t worry guys; use the
second part of the definition. Ask yourself, “Can the mule reproduce?” The mule is sterile and cannot
reproduce; therefore, the horse and donkey are different species.)
Brand new species may form through a process called speciation.
Reproductive isolation leads to speciation. There are three forms of reproductive isolations: behavioral
isolation, geographic isolation, and temporal isolation
Pg. 20
Isolation means to be left alone (If you behave bad in class, I will isolate you from your friends,
muahaha). Anyway, some species of meadowlarks have developed as a result of behavioral isolation.
They perform different behaviors, such as mating songs. Even though the meadowlarks’ habitats
overlap, they will not mate with the other species of bird. Geographic isolation can be seen in two
species of squirrels that were separated geographically by mountains and rivers (this is in your book).
Temporal isolation happens when two or more species reproduce at different times. Your book uses the
example of different species of orchids that produce leaves at different times and must be pollinated
that same day.
HIV Evolution
HIV is a virus that destroys a person’s immune system.
Viruses may contain a DNA or RNA genome, but not both at the same time. HIV is an RNA virus.
Viruses are considered nonliving obligate intracellular parasite. They must get inside of a cell to
reproduce.
HIV is a perfect example of microevolution. The virus is error-prone. It makes a lot of mistakes when
copies of the virus are being made. These mistakes, or mutations, cause new HIV to form. These
mutations allow HIV to always be one step ahead of medications.
Viruses contain a protein coat to protect their genome.
HIV infects all cells that contain CD-4 Receptors. The majority of cells that contain CD-4 receptors are the
Helper T-cells (aka Helper T-lymphocytes)
The Fossil Record
Relative dating allows paleontologists (scientists that study
fossils) to determine whether a fossil is older or younger than
other fossils. Notice that relative dating does not tell us the
absolute age of the fossil. Relative dating can only compare
fossils. The fossils found deeper in the ground are older than the
fossils at the top.
Index fossils are distinctive fossils used to establish and compare the relative
ages of rock layers & the fossils they contain. In other words, we use index fossils
to determine if another fossil is older or younger. On the side is a picture of a
trilobite fossil. These fossils were present in the Paleozoic era. We can use this
fossil as an index fossil to compare other fossil’s ages.
Pg. 21
Radiometric dating relies on radioactive isotopes, which decay, or break down, into stable isotopes at a
steady rate. Carbon dating is an example of radiometric dating that uses the radioactive isotope called
carbon-14 to determine the age of a fossil.
Carbon-14 will decay by half every 5,730 years. In other words, if you start with a 100% sample of
carbon-14 and wait 5,730 years, you will be left with 50% of carbon-14. If you wait another 5,730 years,
then you will have 25% of carbon-14….and so on. This life expectancy of carbon-14, which is reduced by
half every 5,730 years is called the half-life of carbon-14.
A half-life is the time required for HALF of the radioactive atoms to decay.
*Elements with long half-lives are used for dating older fossils.
Potassium-40 has a half-life of 1.26 billion years
Uranium-238 has a half-life of 4.5 billion years
The Origin of Life
SC.912.L.15.8
Describe the scientific explanations of the origin of life on Earth.
SC.912.L.15.10
Identify basic trends in hominid evolution from early ancestors six million years ago to modern humans, including
brain size, jaw size, language, and manufacture of tools.
Endosymbiotic Theory
All living things have cells. Cells are categorized as two types: prokaryotic cells and eukaryotic cells
The prokaryotes are believed to be the first types of cells, which eventually evolved to the eukaryotes.
Prokaryotes do not have a nucleus (pro – before; karyon – nucleus). Eukaryotes on the other hand do
have a nucleus (Eu – true; karyon – nucleus).
Bacteria and Archaea are prokaryotes (cells without a nucleus).
Animals, plants, fungi, and protists are eukaryotes (cells with a nucleus).
Eukaryotic cells contain organelles and are much larger cells than prokaryotes. However, some
organelles appear to be independent cells. The mitochondria and the chloroplasts are two organelles
different from all others.
The mitochondria and chloroplast contain their own DNA
and are very similar to bacteria cells. As a result, it is
hypothesized that mitochondria and chloroplast were
independent cells in the past, and it is believed that the
mitochondria and chloroplast were swallowed by a larger
cell. This resulted in a mutualistic relationship between
these present-day organelles and eukaryotic cells. This is
known as the endosymbiotic theory.
Pg. 22
Miller-Urey Experiment
Stanley Miller and Harold Urey were two scientists trying to
replicate the conditions of early Earth. How could organic
compounds (the key ingredients to life) be formed from
inorganic compounds? They performed the experiment with
inorganic gases that are believed to have been in Earth’s early
atmosphere, such as water vapor, hydrogen gas, methane,
carbon monoxide, and ammonia. Adding electricity to the
experiment resulted in the formation of organic compounds.
Classification
SC.912.L.15.4
Describe how and why organisms are hierarchically classified and based on evolutionary relationships.
SC.912.L.15.5
Explain the reasons for changes in how organisms are classified.
SC.912.L.15.6
Discuss distinguishing characteristics of the domains and kingdoms of living organisms.
Taxonomy
Taxonomy is the study of classification, and the father of taxonomy is Carolus Linnaeus.
People all over the world speak many different languages, and scientists use one language, Latin, to
communicate. Scientists classify organisms using two Latin names. The first name is called the genus
name and the second name is the species name.
Canis latrans (cayote)
Canis lupus (wolf)
Canis familiaris (dog)
Notice that the first name is capitalized; it is called the genus name (Canis); and it is the same for the
cayote, wolf, and dog. This indicates a relationship of common descent between the cayote, wolf, and
dog.
The species name (latrans, lupus, and familiaris) is lower-cased and is unique to each species.
The classification system used in taxonomy is the following:
Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species
(Genus and Species name are in RED color so you remember those are the names used to name
organisms)
Pg. 23
Human and Chimp common ancestor
Phylogeny
Phylogeny or phylogenetics a branch in biology concerned with evolutionary
relationships between species.
Scientists build Darwinian trees (aka phylogenetic trees or cladograms)
based on DNA similarities common to each species.
Look at the phylogenetic tree on the right and notice the human
and the chimpanzee.
Notice that evolution does not say that chimps turned into humans.
Evolution says that humans and chimps share a common ancestor.
A clade is a group of species that includes a single common ancestor and all
descendents of that ancestor. Do you see the blue arrow pointing to the
common ancestor for the human and the chimp? Well, that point, or node,
forms a clade. Every point on the tree above that separates into many species represents a clade. There
are many clades in the phylogenetic tree.
This point, or node, represents a
common ancestor that evolved over
time into various groups that became
its descendents: lizards, turtles,
crocodiles, and birds. This point is
one clade. Every point represents a
clade, or a monophyletic group.
From the picture above notice that birds and crocodiles are more closely related than birds and turtles
because birds and crocodiles share a closer common ancestor.
Who are closer related, mammals and lizards or birds and lizards? To answer this question you need to
find the common ancestor point, or node. The birds and lizards are closer related because they share a
closer common ancestor than mammals and lizards.
Pg. 24
Water
SC.912.L.18.12
Discuss the special properties of water that contribute to Earth’s suitability as an environment for life: cohesive
behavior, ability to moderate temperature, expansion upon freezing, and versatility as a solvent.
Hydrogen and Covalent Bonds
Water is perhaps the most important molecule on Earth. Without water there could be no life.
Water is so important that about 60 – 75% of a person’s body weight is water, and
about 71% of Earth is covered in water. WOW!!
So what makes water so special? Well first of all the molecular formula for water is
H2O. This means that one oxygen atom is covalently bonded to two hydrogen
atoms.
A covalent bond is a chemical bond where atoms share their electrons. Two hydrogen
atoms share electrons with an oxygen atom, and these result in a water molecule,
H2O.
Finally, what makes water so unique is that the big fat oxygen atom does not like to
share its electrons equally with the two small hydrogen atoms. Oxygen is an electron
lover (aka an electronegative atom). Therefore, the electrons will spend more time
around the oxygen atom.
Because water does NOT share electrons equally, we refer to it as having a polar
covalent bond. So, in a regular covalent bond (aka non-polar covalent bond) the
electrons are shared equally, but in a polar covalent bond the electrons are shared
unequally.
Since the electrons spend more time around the oxygen atom, the oxygen atom will
become slightly negative relative to the hydrogen atoms that will become slightly
positive. This is a result of polarity.
Because water has a slightly negative charge and a slightly positive charge, it will act like a magnet and it
will stick to other water molecules. The attraction between one water molecule and another water
molecule is a result of hydrogen bonds (H2O ----- H2O)
*Please pay special attention to the difference between the covalent bond in H2O and the
hydrogen bond between H2O----H2O. Students get these two concepts wrong on tests. The polar
Pg. 25
covalent bond is for the 2 hydrogen atoms and the 1 oxygen atom, while the hydrogen bond is for
several water molecules that attract each other like magnets.
The top part was actually the hardest part to understand…Now for the easier parts of water.
Water is the universal solvent. A solvent is a substance in greater quantity that will
dissolve another substance known as the solute. Water is the solvent and sugar is
the solute. If you put sugar in water, the water will dissolve it.
Properties of Water
Water holds on to other water molecules as hard as they can (water buddies). This property of water is
called cohesion. Cohesion is when water sticks to water. The water strider is able
to walk on water because water will try to hold on to each other to prevent the
water strider from separating them.
Water can also stick to other substances other than itself. This is called adhesion. Isn’t water such a
friendly molecule? If you have a bathtub and a curtain, wet the curtain and cover the edge of the
bathtub to prevent water from spilling outside and wetting the floor. The wet curtain will stick to the
wall. This is adhesion.
or
When cohesion and adhesion work together, water can climb up the roots of plants and spread up and
out towards the leaves. The movement of water up the roots to the stem and leaves is called capillary
action.
Pg. 26
Water has a high surface tension. This means that the water buddies will hold on to each other and
become tense. Moral of the story…Do not jump into a pool on a belly position, or the water will smack
you silly.
(this is going to hurt…)
(look how the tension holds the coin)
The next water property is density. Solid water (ice) is actually LESS DENSE than liquid water. This
allows ice to float. This is important because when the ocean freezes, the ice rises and the ocean
animals can still swim underwater. Water is actually densest at 4 degrees Celsius (this is cold water but
not frozen water).
The last water property is high heat capacity. Water can hold a lot of heat. This is
why our bodies carry so much water…So we do not burn or melt when we go out in
sunny Florida; moreover, the water will keep you from freezing if one day you
decide to go to New York during the holidays.
Water freezes at 0 degrees Celsius and boils at 100 degrees Celsius.
Pg. 27
pH
(literally stands for “power of hydrogen”)
The pH is a way to determine whether something is an acid, a base, or neutral.
The pH scale is logarithmic (that is a fancy way of saying you multiply by 10 for each increase or
decrease). For example: a pH of 2 is 100 times more acidic than a pH of 4 (10 x 10 = 100)
The pH scale ranges from 0 to 14, and 7 is neutral. Water has a neutral pH of 7.
A pH below 7 is considered acidic, while a pH above 7 is considered basic (aka alkaline).
The more hydrogen ions, H+, in a solution compared to hydroxide ions, OH-, the more acidic the
solution is.
The more hydroxide ions, OH-, in a solution compared to hydrogen ions, H+, the more basic the
solution is.
Every living thing has an optimal level of pH. This is level where the organisms can
actually live and survive. If the pH changes below or above the optimum range, the
organism may die. For example, blood has a pH range of 7.35 – 7.45. If blood pH
drops or rises, a person may die!
Your body needs to keep your blood at a pH between 7.35 – 7.45, or you may die if the
pH drops below 7.35 or rises above 7.45. How does your body keep the pH at this
range? Your body uses something called a buffer. A buffer is a compound used to
maintain the pH at a certain range.
When the pH becomes too acidic, the buffer will release basic ions to increase the pH back to its range.
When the pH becomes too basic, the buffer will release acidic ions to drop the pH back to its range.
Pg. 28
Biochemistry
SC.912.P.8.7:
Interpret formula representations of molecules and compounds in terms of composition and structure.
SC.912.P.8.12:
Describe the properties of the carbon atom that make the diversity of carbon compounds possible.
SC.912.L.18.1
Describe the basic molecular structures and primary functions of the four major categories of biological
macromolecules.
SC.912.L.18.2:
Describe the important structural characteristics of monosaccharides, disaccharides, and polysaccharides and explain
the functions of carbohydrates in living things.
SC.912.L.18.3:
Describe the structures of fatty acids, triglycerides, phospholipids, and steroids. Explain the functions of lipids in
living organisms. Identify some reactions that fatty acids undergo. Relate the structure and function of cell
membranes.
SC.912.L.18.4:
Describe the structures of proteins and amino acids. Explain the functions of proteins in living organisms. Identify
some reactions that amino acids undergo. Relate the structure and function of enzymes.
A macromolecule is a large molecule.
There are 4 macromolecules: carbohydrates, lipids, proteins, and nucleic acids.
Carbohydrates
Carbohydrates come from plants and are the body’s main source of energy.
Examples: rice, tomatoes, bread, pizza, beans, bananas, etc…
Carbohydrates contain the elements carbon, hydrogen, and oxygen in a 1:2:1 ratio.
Glucose is a simple sugar. It is a carbohydrate. Count the number of
carbon, hydrogen, and oxygen atoms in glucose. Glucose has 6
carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms. Thus, the
molecular formula for glucose is C6H12O6. Notice that glucose has the
1:2:1 ratio because the number of carbon and oxygen atoms is the
same, while the number of hydrogen atoms is twice as much.
Sometimes simple carbohydrates like glucose are written as a ring (right), while other times it is written
in a linear manner (left).
Sugars typically end with the suffix –ose. This is how you know it is a sugar.
Examples of sugars: glucose, fructose, galactose, maltose, cellulose.
Glucose is a one sugar molecule. Glucose is a monosaccharide.
Lactose, the sugar in milk, is made up of two different sugars. Lactose is a disaccharide.
Pg. 29
Cellulose is the sugar that makes the cell wall of plants. Cellulose is made up of many repeating sugars.
Cellulose is a polysaccharide.
Lipids
Lipids are fats, sterols, waxes, etc…Keep it simple, lipids are fats.
Lipids contain the elements carbon, hydrogen, and oxygen. Lipids have the same exact elements are
carbohydrates. Oh, oh…How do we tell the difference? Lipids do NOT have the 1:2:1 ratio, and lipids
tend to have more carbon and hydrogen bonds while having very few oxygen atoms.
Lipids hate water. They are hydrophobic.
The functions for lipids include longer term energy, insulation, and water proof.
Lipids can be saturated with hydrogen atoms, or they can be unsaturated
by hydrogen atoms.
The saturated fat is a solid at room temperature and less healthy than the
unsaturated fat, which is a liquid at room temperature.
Proteins
Proteins are made up of monomers called amino acids.
Amino acids, and thus proteins, contain the elements carbon, hydrogen, oxygen, and nitrogen. Notice
that proteins have one more element when compared to carbohydrates and lipids, and that extra
element is nitrogen.
All amino acids have 4 things in common
1. Amine group (NH2)
2. A central carbon atom
3. 1 hydrogen atom attached to the central carbon atom
4. A carboxylic acid group (COOH)
Pg. 30
*The only thing that is different from one amino acid to the next is the side chain known as the R group.
Check out the R groups on the picture below. The R group for Alanine is CH3 while the R group of the
other amino acids is much more complicated.
If you want to connect two amino acids (or ANY other molecule), you need to
remove a water molecule. Removing water is called dehydration synthesis. If
you want to break a molecule, just add water. Adding water is called hydrolysis.
So, water tends to break things, and removing water tends to form things.
Examples of proteins include enzymes, antibodies, hormones, and food (meat).
Nucleic Acids
Nucleic acids are composed of monomers called nucleotides. Nucleic acids contain the genetic
information of an organism.
Nucleotides, and thus nucleic acids, contain the elements carbon, hydrogen, oxygen, nitrogen, and
phosphorus. If you see a phosphate group, or simply a phosphorus atom, you should select the
nucleotide/nucleic acid choice.
There are two kinds of nucleic acids: DNA and RNA.
The NA in DNA and RNA stands for nucleic acid…but I am sure you knew that since you are very smart.
DNA
Nitrogenous Bases: A, T, C, G
Double Stranded
Deoxyribose sugar
Deoxyribonucleic Acid
Phosphate group
RNA
Nitrogenous Bases: A, U, C, G
Single Stranded
Ribose sugar
Ribonucleic Acid
Phosphate group
Notice that DNA and RNA have the phosphate group in common and the bases A, C, and G. Everything
else is different.
Pg. 31
Cytology
SC.912.L.14.1
Describe the scientific theory of cells (cell theory) and relate the history of its discovery to the process of science.
SC.912.L.14.2
Relate structure to function for the components of plant and animal cells. Explain the role of cell membranes as a
highly selective barrier (passive and active transport).
SC.912.L.14.3
Compare and contrast the general structures of plant and animal cells. Compare and contrast the general structures
of prokaryotic and eukaryotic cells.
Introduction
The story of the cell begins with Robert Hooke and his invention of the microscope. Hooke placed a
piece of a cork (like from a wine bottle) under his microscope and noticed that the structure of the cork
under the microscope looked like jail cells. Hooke decided to use the word “cell” from there on.
After the microscope was invented, and we were able to study cells, the cell theory was born.
The cell theory states 3 things:
1. All living things are composed of cells (bacteria are cells, so they are ALIVE)
2. Cells are the basic unit of structure and function in living things
3. New cells are produced from existing cells (“Omnis Cellula e Cellula” – Rudolf Virchow)
*Viruses are not cells, nor do they contain cells; therefore, viruses are NONLIVING.
Cells are divided into two categories: Eukaryotic cells and Prokaryotic cells
-Eukaryotes = True Nucleus (these cells have a nucleus)
- Prokaryotes = Before Nucleus (these cells do not contain a nucleus)
There are 4 Eukaryotes: Animals, Plants, Fungi, & Protists
There are 2 Prokaryotes: Bacteria & Archaea
Eukaryotic Cells
Nucleus
Yes
Organelles
Yes
Ribosome
Yes
Plasma Membrane
Yes
Size
Bigger than Prokaryotes
Scientists use a compound light microscope to study cells.
Guess why they call it a compound light microscope…It
uses “light” to view the specimen, and it uses multiple
lenses (compound).
All you need to know about this type of microscope is to
multiply the lenses that you use to get your total
magnification, or power. The ocular lens found within the
eyepiece has a magnification of 10X. Then you will select
one of the three objective lenses: 4X, 10X, or 40X. Finally
Prokaryotic Cells
No
No
Yes
Yes
Smaller than Eukaryotes
Pg. 32
multiply the ocular lens with the objective lens that you decided to use.
Total Magnification: 10X x 40X = 400X
If a researcher at a university or private company is interested in looking inside the cell to investigate the
structure and function of each organelle, then he or she will need a more powerful microscope.
The electron microscope is more powerful than the light microscope. Instead of using light, the electron
microscope fires a beam of electrons.
Two types of electron microscopes:
1. Transmission Electron Microscope (TEM): lets you see inside a cell
2. Scanning Electron Microscope (SEM): lets you see the 3D outside of the cell
The downfall to the electron microscope:
1. Too expensive (you will not find one in High School)
2. You must use nonliving preserved cell specimens (no living cells
allowed)
Now we are ready to compare two special eukaryotic cells: the animal cell
and the plant cell.
Animal cells tend to be round (generally speaking) because they do not
have a cell wall.
Some animal cells have a tail called a
flagellum. Flagella allow cells to swim.
Sperm cells have flagella.
Plant cells, on the other hand, have a cell wall, chloroplast, and a large central vacuole.
Cytoskeleton of the Cell
Just as we have bones and muscles, the cell has its own skeleton, which is called the cytoskeleton.
The cytoskeleton is made up of microtubules, intermediate filaments, and microfilaments (aka actin
filaments)
Microtubules contain the protein tubulin & they participate in cell
division & cell movement
Examples: Centrioles, Cilia & Flagella.
Pg. 33
Microfilaments contain the protein actin and are found in muscle cells. They also support cells & help
them move
Intermediate filaments are intermediate in size to the microtubules and microfilaments. You do not
need examples of intermediate filaments for the test, so don’t worry about these.
Pg. 34
Animal Cell (a type of Eukaryotic Cell)
rRNA created & used
for protein assembly
Makes lipids &
detoxifies poisons
“Brain” of cell;
command center (DNA)
Cell membrane made
of phospholipid
bilayer regulates what
goes in or out of cell
Cellular
Respiration
(energy)
Releases spindles
that attach to
chromosomes
during cell
division
Finish making proteins
made on ribosome
Makes proteins
Protein sorting &
packaging (aka FEDEX
or UPS)
*Just because a cell has a cell wall does not mean it is a plant. Fungi and bacteria may have cell walls as
well.
In plants the cell wall is made of cellulose.
In fungi the cell wall is made of chitin.
In bacteria the cell wall is made of peptidoglycan.
Moral of the story… You need to look for more organelles to be 100% on the test that it is a plant. If you
notice that the organism has a cell wall, chloroplast, and central vacuole, then you can say that it is a
plant.
By the way, organelles are the organs of cells. The word organelle literally means “little organ.”
Pg. 35
Plant Cell (a type of Eukaryotic Cell)










Organelles:
Nucleus: cell’s command center (home of DNA)
Nucleolus: ribosomal RNA is assembled (rRNA)
Cytoplasm: area outside of the nucleus where the organelles are found
Plasma Membrane: the cell membrane regulates what goes in and out of the cell
Rough Endoplasmic Reticulum (RER): contains ribosomes & synthesizes proteins for cells to
export
Smooth Endoplasmic Reticulum (SER): does not contain ribosomes and is used to synthesize
fats and detoxification of drugs
Ribosome: factories for making proteins
Golgi Apparatus: modify, sort, and package proteins made in the rough endoplasmic reticulum.
Mitochondria: makes energy for the cell & contains its own DNA (cellular respiration)
Lysosomes: digest old organelles, macromolecules, and remove junk from the cell.
Pg. 36


Vacuoles: store materials, such as water, salts, proteins, and carbohydrates. They are like a
closet or kitchen cabinet. Plants have a large central vacuole, and animal cells have many small
vacuoles
Chloroplasts: converts sunlight into chemical energy & contains its own DNA (photosynthesis)
Cell Transport
The plasma membrane, or cell membrane, is found in every type of cell. It does not matter if the cell is
eukaryotic or prokaryotic. All cells must have a membrane. The plasma membrane regulates what goes
in or out of the cell.
The plasma membrane is made up of two layers of phospholipids, some proteins embedded in the
membrane, cholesterol, and some carbohydrates. This is referred to as the fluid mosaic model.
The two layers of phospholipids is called the phospholipid bilayer. Each phospholipid contains a water
loving phosphate head (hydrophilic) and two water hating lipid tails (hydrophobic).
The plasma membrane is selectively permeable (aka semi-permeable). This means that the membrane
allows some things to go through it and not others.
The following can pass through the plasma membrane phospholipid bilayer:
1. Small Non-polar molecules (e.g. oxygen molecule, carbon dioxide, methane)
2. Lipids (fats)
The following cannot pass through the plasma membrane phospholipid bilayer:
1. Large molecules (e.g. glucose)
2. Polar molecules (e.g. water)
3. Charged particles (e.g. Na+, Cl-, Ca2+)
Pg. 37
Diffusion is the movement of particles from an area of higher concentration to an area of lower
concentration. There is simple diffusion and facilitated diffusion.
Diffusion does NOT require energy for it to occur. Diffusion is a form of passive transport.
No one likes to be crowded. Well, chemicals do not like to
be crowded either. Chemicals are a bit claustrophobic, so
they will spread out to less crowded areas. This sums up
what diffusion is.
If someone releases a bad odor in the front of the
classroom, eventually someone in the back of the room will
smell it. This is called simple diffusion. It is when molecules
spread to less concentrated areas.
Sometimes chemicals need help getting through the plasma
membrane from an area of higher concentration to an area
of lower concentration. This type of diffusion will occur if a
helper protein can make it happen. This is facilitated
diffusion.
Osmosis is the movement of water from an area of higher water concentration to an area of lower
water concentration through a selectively permeable membrane. Osmosis does not require energy; it is
another example of passive transport.
Look at the picture below. The U-shape apparatus is divided into the left and right side by a thin
selectively permeable membrane. There is water on the left and right side as well as salt (purple circles).
Question: Where is there more water in picture 1? Many students will say that there is the same
amount of water in picture 1; however, there is actually more concentration of pure water on the left
because there is less salt. Therefore, the water from the left will start to cross the membrane and go
over to the right side. You can see the water moving to the right in picture 2. This movement is osmosis.
Picture 1
Picture 2
Hypotonic solution: a water solution
with little amount of salt.
Hypertonic solution: a water solution
with a lot of salt.
Isotonic solution: a water solution
with equal concentrations of water
and salt.
Pg. 38
You can see two real life examples of osmosis below:
1. When the red blood cell is placed in a hypertonic solution (a water solution with lots of salt), the
water from within the red blood cell will escape the cell & the cell will shrink.
2. When the red blood cell is placed in an isotonic solution (a water solution with equal water and salt),
the water will move in and out of the red blood cell at the same rate resulting in a normal cell.
3. When the red blood cell is placed in a hypotonic solution (a water solution with very little salt), the
water from the solution will enter the cell causing the cell to become huge and explode.
*Remember that diffusion and osmosis are examples of passive
transport (no energy required).
Active transport on the other hand, requires energy because the
particles are moving against their concentration gradient. In other
words, the particle is going from a less crowded area to a more crowded
area. The sodium-potassium pump is an example of active transport in
the body.
Sometimes cells need to bring in or out substances that are too large. When this happens, the cell finds
another way to get things in or out.
Endocytosis means to “bring in the cell.” Cells pinch and fold their entire plasma membrane to bring
something in. There are three different types of endocytosis.
1. Phagocytosis: “cell eating” – the cell brings in large food particles
2. Pinocytosis: “cell drinking” – the cell brings in liquids
3. Receptor-Mediated Endocytosis: the cell will bring in molecules that attach to cell receptors.
Pg. 39
Exocytosis is when the cell takes large substances out of itself.
Pg. 40
Homeostasis
Introduction
Homeostasis refers to the body’s ability to maintain relatively stable internal conditions even though
the outside world changes continuously. Homeostasis is regulated via the nervous system and endocrine
system.
I like to think of homeostasis as a balance. For example, when it is really hot outside,
your body temperature begins to rise above normal levels. As a result, your body has to
try to bring back your body temperature to normal levels. Your body accomplishes this
task through the use of sweat. Sweat cools the body down.
What if your body cannot balance itself back to a stable condition? Disease is a result of
homeostatic imbalance. For example, in some people the pancreas does not produce insulin. This causes
blood sugar levels to spike beyond normal. Because the pancreas cannot place the body back into
balance, a disease called diabetes mellitus type 1 occurs.
Negative Feedback
Negative feedback is the body’s way of regulating itself by doing an opposite action. For example, when
you run a mile the body uses up a lot of oxygen to feed muscle cells. As a result, your body demands
that your heart beats faster and you breathe harder. In this example, the decrease in oxygen forces your
respiration and heart rate to increase. Since we have one action increasing and the other decreasing, we
call this homeostatic mechanism negative feedback.
Positive Feedback
In positive feedback the body will regulate itself by enhancing a response. For example, during
childbirth, a hormone called oxytocin is released. Oxytocin causes contractions, but the contractions
cause more oxytocin to be released, which causes more contractions, which causes more oxytocin to be
Pg. 41
released….you get where this is going, I hope. This process will continue to occur until the baby is
released.
*Both positive and negative feedback try to establish homeostasis (balance).
Pg. 42
The Nervous System
SC.912.L.14.26
Identify the major parts of the brain on diagrams or models.
Introduction
The nervous system is made up of many nerve cells called neurons.
These nerve cells allow electrochemical signals to be transmitted via nerves to all parts of the body.
The brain is the “boss” of this system.
Functions of the brain: thinking, talking, movement, listening, sensing, seeing, personality, and many
more.
Two Nervous Systems
Central Nervous System: brain and spinal cord
Peripheral Nervous System: all the nerves that branch off the spinal cord
Brain
Memorize all the parts shown below.
The 4 lobes make up the cerebrum
The pons and medulla make up the brainstem
The cerebellum (aka “little brain”) is towards the back of the head next to the brain stem.
Pg. 43
Fun fact: It is technically incorrect to say, “I love you with all my heart.” The proper technical term
should be, “I love you with all my brain.”
The Cardiovascular System
SC.912.L.14.36
Describe the factors affecting blood flow through the cardiovascular system.
Introduction
The cardiovascular system is made up of the heart (cardio) and the blood vessels (vascular).
The heart is a pump that pumps blood throughout the body.
Blood is always red and travels through arteries, veins, and capillaries.
When blood has oxygen we call it oxygenated blood (this blood is colored red in books)
When blood has no oxygen we call it de-oxygenated blood (this blood is colored blue in books)
Blood Vessels
Arteries are large blood vessels that carry blood away from the heart and to the rest of the body.
- arteries can constrict (get smaller) or dilate (get wider) due to many factors, such as those from the
nervous system
- arteries have blood pressure, so they have a pulse that can be felt in several places of the body, such as
on the wrist by the side of the thumb (measured in beats per minute)
-arteries usually contain oxygenated blood (red in books), but there are exceptions.
Veins are large blood vessels that carry blood to the heart from the body.
-veins do not have much blood pressure, so they do not have a pulse that can be felt
-veins usually contain deoxygenated blood (blue in books), there are exceptions
-since veins have little pressure, they contain valves to prevent gravity from pulling the blood back
down.
Capillaries are tiny blood vessels with two major functions:
1. Capillaries connect arteries and veins
2. Capillaries allow the diffusion of gases between the
cardiovascular system and respiratory system
Heart
The human heart is a pump about the size of your first.
The human heart contain 4 chambers: right & left atria and right &
left ventricles
Pg. 44
The human heart contains 4 valves to stop the blood from going backwards
Blood Circulation
There are two main types of circulations: pulmonary circulation and systemic circulation
In pulmonary circulation, the right side of the heart pumps de-oxygenated blood to the lungs to pick up
the oxygen. The oxygenated blood returns to the left side of the heart.
In systemic circulation, the left side of the heart, which contains oxygenated blood, sends the blood out
of the Aorta to the rest of the body.
Coronary Circulation
If the heart provides oxygenated blood to the whole body, then who provides oxygenated blood to the
heart? The heart recycles some oxygenated blood to feed itself. This oxygen-rich blood is passed along
small arteries that encircle the heart. These are called coronary arteries. Coronary means crown.
The de-oxygenated blood is then passed to the coronary veins. The coronary arteries and veins together
form the coronary circulation of the heart.
Heart attacks occur when coronary arteries become clogged with fat and a part of the heart muscle
dies as a result of the lack of oxygen.
Pg. 45
Blood
Blood is a liquid composed of cells and plasma that is used to transport oxygen and collect waste to and
from the body.
Red blood cells (erythrocytes) pick up the oxygen from the
lungs & deliver it to the rest of the body. Red blood cells also
pick up the waste, carbon dioxide, and deliver it in the lungs
for you to breathe it out.
White blood cells fight infection. Some white blood cells are
nonspecific and fight any type of germ (example:
macrophages). Other white blood cells are specific and
recognize a variety of infectious agents (T and B cells).
Platelets are not cells. Platelets are cell fragments used in
blood clotting. Thanks to platelets, we do not bleed to death
from a small paper cut.
Blood Pressure
Blood pressure is the force felt on ARTERIES (not
veins) as blood goes through.
Blood pressure is a result of having a beating heart. If
you are dead, your heart won’t beat, and you will not
have blood pressure.
The contraction of the heart’s ventricles forces the
blood out of the heart. This is called systolic blood
pressure. It is highest pressure squeezed out of the heart.
When the heart relaxes, there is still blood pressure in
the arteries. This pressure is called diastolic blood
pressure.
Blood pressure can rise due to fear or strong emotions. It
can also rise due to old age. Elderly people usually have
higher blood pressure than young people because of
diseases like arteriosclerosis and atherosclerosis.
To decrease your blood pressure, eat right (low fat),
exercise, & don’t smoke.
Pg. 46
Heart Rate & Blood Pressure Relationship and
Disease
Atherosclerosis is a cardiovascular disease in which plaque
builds up in your arteries. This fat makes the inside of
arteries thin, resulting in less blood flow. If the fat continues
to build up, it may clog the artery, resulting in a heart attack.
The build-up of plaque causes a lack of oxygen throughout
the body. When your cells cannot breathe, they will send
signals to the heart to pump faster and harder. The faster and harder the heart pumps, the more
pressure.
Faster Heart Beat = More Blood Flow = Higher Pressure
Generally Speaking
Slower Heart Beat = Less Blood Flow = Less Pressure
Infections typically cause fevers, which lead to an
increase in the heart rate.
Blood thickness is called viscosity. The more viscous the blood, the
thicker it is. Older people’s blood tends to be more viscous than
younger people. High blood viscosity leads to high blood pressure
and other cardiovascular problems.
High viscosity leads to increased resistance of blood flow, which
causes a slow blood flow. High viscosity may be caused by a lot of red
blood cells in the blood. The more red blood cells, the more traffic
and the slower blood travel.
Remember that when people get older, their blood becomes thicker (viscous), their blood pressure
increases, their arteries become less elastic (arteriosclerosis – hardening of the arteries), diseases are
more common, and the heart becomes less efficient.
*Don’t confuse arteriosclerosis (hardening of artery) with atherosclerosis (fat in artery)
Pg. 47
The Immune System
SC.912.L.14.6
Explain the significance of genetic factors, environmental factors, and pathogenic agents to health from the
perspectives of both individual and public health.
SC.912.L.14.52
Explain the basic functions of the human immune system, including specific and nonspecific immune response,
vaccines, and antibiotics.
Introduction
The immune system is made up of cells, organs, and lymph that protect you from getting sick.
White blood cells (leukocytes) fight infections. There are many varieties of white blood cells and each
has their own function.
Never Let Monkeys Eat Bananas - is a mnemonic to help you memorize different types of white blood
cells in order from greatest to the least in the body.
Neutrophil (65%)
Lymphocyte (25%)
Monocyte (6%)
Eosinophil (3%)
Basophil (1%)
Lines of Defense
The first line of defense is nonspecific. This means that this barrier will protect you from any type of
germ: skin, mucous membrane, stomach acid, sweat, tears, & saliva.
If the invader manages to break through the first line of defense and enter the body, the second line of
defense goes into action. The second line of defense is nonspecific. Thus, just like the first line, the
second line will protect you from any type of germ. The second line of defense involves fever and
inflammation. There are ways to fight the germ.
Finally, if the first and second line of defense fails, the body must send the soldiers to recognize the
invaders and destroy them. The third line of defense is specific. This means that the body now
understands specifically the invader & seeks to destroy it. The third line of defense is made up of the
lymphocytes: T and B cells.
The lymphocytes
Usually, a large white blood cell called a macrophage, presents an antigen to the helper T-cells. An
antigen is a piece of protein found on the surface of the pathogen.
The helper T-cell then seeks a B-cell and activates it. Once the B-cell is activated, it begins producing
antibodies to fight the invading pathogen.
Pg. 48
The Helper T-Cell then activates
the B-cell, which produces
antibodies
Medications to Fight Disease
Antibiotics (not antibodies), are used to kill infections caused by bacteria. You should not use antibiotics
for other diseases such as the flu, which is caused by a virus.
-Examples of Bacteria-caused Diseases: strep throat, chlamydia, gonorrhea, salmonellosis, E. coli, etc…
- Antibiotic examples: Penicillin, Ciprofloxacin, Amoxicillin, Azithromycin, Tetracycline, etc…
Antivirals are used to treat viral infections.
-Examples of Viral Diseases: Flu, Common Cold, HIV, Herpes, etc…
-Antiviral examples: Tamiflu, Acyclovir, Interferon, Truvada
Antifungals are used to treat fungal infections (mycoses).
-Examples of Diseases caused by Fungi: Ringworm, Athlete’s Foot, Jock Itch, Dandruff, Yeast infections,
etc…
-Antifungal examples: Zinc Pyrithione (Head & Shoulders), Ketoconazole, Selenium Sulfide, Clotrimazole
*There are many more types of diseases and medications, but I will not write them all. However,
understand that bacteria, viruses, and fungi are not the only disease-causing agents.
Types of Immunity
Immunity refers to being able to fight disease. If your body is immune to the chicken pox virus, then you
will not get sick from chicken pox.
In active immunity, your body actively produces antibodies to fight disease.
There are two types of active immunity: naturally acquired and artificially
acquired.
-Naturally Acquired Active Immunity: Your body naturally encounters a disease,
like the flu, and naturally produces antibodies to fight the disease.
-Artificially Acquired Active Immunity: The doctor vaccinates you with a
weak or inactive pathogen (e.g. flu shot) and your body produces
antibodies to fight this disease in the future if it ever encounters it. This is
Pg. 49
called artificial because your body is not naturally encountering the pathogen; rather the doctor is
injecting it in you to produce an immune response.
In passive immunity, your body does not produce its own antibodies to fight disease. These antibodies
are brought into the body by other means. There are two forms of passive immunity: Naturally acquired
and artificially acquired.
-Naturally Acquired Passive Immunity: When a mother breast
feeds her baby, she is naturally passing on her antibodies to her
baby. These antibodies will protect the baby against diseases.
Notice that this is “passive” because the baby did not actually
make antibodies. It is “natural” because the baby naturally
received antibodies through breast milk while feeding.
- Artificially Acquired Passive Immunity: When a snake bites
someone and injects its poison, there is no time for the body to make
its own antibodies. Therefore, anti-venom must be administered
quickly to the patient. Anti-venom are antibodies that are injected
into an individual to trigger an immune response. This is “passive”
because the individual is not making antibodies on his or her own. It
is “artificial” because the doctor injects this into the individual
instead of the individual acquiring it naturally.
Vaccines
A vaccine is an injection that contains an inactive or weak form of a pathogen.
Some vaccines are very effective in preventing or eradicating diseases. The small-pox vaccine, for
example, has helped the world eliminate the small-pox virus. Small-pox literally does not exist anymore.
Other viruses, like the Flu, keep coming back year after year. Each year, there needs to be a brand new
flu vaccine. Why? This is because the flu is a virus that is constantly mutating, or changing. Every year
there is a new strain of the flu virus.
Pg. 50
Viruses
Viruses are considered nonliving entities because they do not contain cells, nor are they cells.
Viruses may contain DNA or RNA, but not both at the same time. Therefore, there are RNA viruses like
HIV and DNA viruses like Herpes.
Viruses contain a protein coat that protects their DNA or RNA.
Viruses are considered intracellular parasites. In other words, they must go inside your cells
(intracellular) to cause disease. They are little terrorists that hijack cells!
Viral Life Cycles
-Lysogenic Cycle – Some viruses, like the chicken pox virus (a herpes virus), stay
inside your cells “asleep.” They do not do anything while they are “asleep” or
“dormant.” This is sleep is the lysogenic cycle. People who have had the chicken pox virus (Varicella
Zoster Virus) have the virus inside of them still!
-Lytic Cycle – When the chicken pox virus awakens from its sleep, it begins
to replicate very quickly causing your cells to burst. Millions of chicken pox
viruses are shed and a rash known as shingles appears. This insane
replication of the viruses that leads to cell death is called the lytic cycle.
*The chicken pox virus is not the only viruses who undergoes the lysogenic and lytic cycle. This is just
ONE example.
HIV and AIDS
The Human Immunodeficiency Virus, or HIV, is a retrovirus composed of RNA.
Retroviruses work backwards from the central dogma of molecular biology, which states that
DNA RNA  Protein. The retroviruses follow this path RNA  DNA RNA  Protein.
HIV destroys any cell in the body with CD4+ receptors. Therefore, HIV can infect Helper T-cells,
monocytes, macrophages, and dendritic cells because they all have CD4+ receptors.
The most common cell that HIV infects and destroys is the Helper T-cell (a.k.a. Helper T-Lymphocyte)
Pg. 51
HIV is the virus that causes AIDS, or Acquired Immune Deficiency Syndrome. After HIV destroys a
person’s immune system, the person begins to get really sick and develop weird infections that a
healthy person would normally never get. These strange infections are called opportunistic infections
because they take the opportunity when you are really sick to come out.
Examples of AIDS opportunistic infections: Kaposi’s sarcoma, Pneumocystis Jirovecii Pneumonia
(formerly known as PCP), candidiasis, etc…
PCP or PJP
Kaposi’s Sarcoma
Oral Candidiasis
HIV is a sexually transmitted infection. It is spread through bodily fluids, such as semen, vaginal fluid,
breast milk, and blood.
When a person has unprotected sex, he or she usually has to wait about 3 months before getting tested
for HIV. This is because the most common HIV tests do not actually look for the virus. These HIV tests
look for the antibodies that your body makes to fight the virus.
1 line = HIV Negative
2 lines = HIV Positive
Pg. 52
Botany
SC.912.L.14.7 Relate the structure of each of the major plant organs and tissues to physiological processes.
Plant Evolution
Introduction
Plants are classified as bryophytes and tracheophytes.
The bryophytes are simple and nonvascular plants.
The tracheophytes are complex and vascular plants.
To be considered a vascular plant, the plant needs to have true roots, true stems, and true leaves.
The ancestor of all plants is the green algae. Algae are normally considered protists, but scientists have
decided to classify green algae as plants.
Bryophytes
Bryophytes are nonvascular plants (no true roots, stems, or leaves).
There are three categories of bryophytes: mosses, liverworts, and hornworts.
Mosses
Liverworts
Green Algae – The ancestor of all plants
Hornworts
Pg. 53
Tracheophytes
Tracheophytes are vascular plants; they have true roots, stems, and leaves.
They are divided into seeded and seedless plants.
The seedless tracheophytes are the ferns (pteridophytes).
The seeded tracheophytes are the gymnosperms and angiosperms.
Fern
The gymnosperms (naked seeds) are the non-flowering plants. They produce cones, which contain their
seeds. Examples of gymnosperms are conifers, cycads, Ginkgo, and Gnetales.
The angiosperms (covered seeds) are the flowering plants below. They are the most abundant in the
world due to their incredible evolution of beautiful colors, smells, and delicious fruits.
The ovary of a flower becomes fertilized and yields a fruit. There are over 250 thousand species of
flowering plants in the world. That is a lot!
Flower Anatomy
The stamen is the male part of the flower (notice it ends in
men). The stamen is composed of the anther and the
filament. The pollen is on the anther. This flower to the right
has a total of 6 stamen.
The Carpel or Pistil is the female part of the flower. It is
composed of the stigma (sticky top part), the style, and the
ovary. The ovary has ovules which become fertilized to
produce a juicy fruit.
*You need to memorize where each part goes.
Pg. 54
Angiosperm Classification: Monocots and Dicots
Flowering plants (angiosperms) can be further divided into monocots and dicots, which make up about
98% of all flowering plants.
Monocots and dicots have 1 or 2 cotyledons. A cotyledon is the embryonic seed leaf. It stores food for
the embryo in the seed.
Monocots, or monocotyledons, have one cotyledon.
Dicots, or dicotyledons, have two cotyledons.
You may determine if the angiosperm is a monocot or dicot by looking at certain features, such as the
number of floral petals, the number of cotyledons, the vascular bundles, root system, and veins.
Pg. 55
Plant Characteristics, Structure & Function
As far as this class and the Biology EOC are concerned, all plants have the four following things
1. Chloroplast – used to convert sunlight into chemical energy (photosynthesis)
2. Large central vacuole – is large structure that stores water, food, nutrients and waste.
3. Cell wall – The cell wall in plants is made up of a polysaccharide called cellulose.
4. Waxy cuticle – protects plants from water loss.
The Leaf
The leaf is a plant organ. It is the site of photosynthesis.
The leaf of a plant contains an upper and lower layer called the epidermis. The epidermis is in charge of
producing a waxy substance called the cuticle, which protects plants from water loss. Together, the
epidermis and cuticle protect the plant from insects, bacteria, and other pests.
The epidermis of plants contains guard cells, which open and close to let gases and water vapor in and
out of the leaf. The hole which the guard cells open and close is called the stoma (stomata is plural).
The mesophyll is a part of the leaf divided in two parts: palisade mesophyll and spongy mesophyll.
The palisade mesophyll contains vertically elongated palisade cells with many chloroplasts for
photosynthesis.
The spongy mesophyll contains irregular cells that also photosynthesize, but their main function is to
communicate with the guard cells (stomata), causing them to open or close, depending on the
concentration of gases.
Leafs contain large veins called vascular bundles. Within these vascular bundles are the xylem and
phloem. The phloem transports food from the leaves & down to the rest of the plant. The xylem
transports water from the roots and up to the rest of the plant
Phloem in, Xylem out
Pg. 56
Plant Tissues
Plants have cells that are actively dividing. These cells are called
meristems.
The meristems allow two types of growths: primary growth and
secondary growth.
Primary growth increases the length of a plant. The tissues that cause
primary growth are the apical meristems and are located in the tips of
the roots and stems.
Secondary growth occurs due to the lateral meristems (axillary
meristem), which increase the width of the plant. These are located on
the sides of stems and roots.
The following 4 plant tissues should be known
1. Dermal Tissue: outer layer of cells which protect the plant from water loss and from fungi and
bacteria.
2. Vascular tissue: transports water, nutrients, and other materials through the plant
3. Ground tissues: tissues that the vascular tissue is embedded in
4. Meristematic Tissue: cells that divide
Pg. 57
Life Cycle of Plants
Plants have an alternation of generation life cycle, which means that they spend half of their lives as
haploids and part of their lives as diploid.
Diploid and haploid are terms used in genetics to refer to the amount of DNA. For example, humans
have 46 pieces of DNA called chromosomes. The 46 in humans is the diploid number. On the other hand,
a sperm or an egg cell contains half as much information, so a sperm or egg cell contains 23
chromosomes (half of much). Thus, sperm and egg cells are haploid because they contain half as much
DNA.
The haploid plant is called a gametophyte
because it produces haploid gametes. Gametes
are sex cells (sperm and egg).
The diploid plant is called the sporophyte, but it
produces haploid spores (not diploid spores…be
careful).
The haploid spores produced by the sporophyte
mature to become the gametophyte plant. The
gametophyte plant then produces sperm and egg,
which eventually become a sporophyte after
fertilization and maturation.
Pg. 58
Enzymes
SC.912.L.18.11
Explain the role of enzymes as catalysts that lower the activation energy of biochemical reactions. Identify factors,
such as pH and temperature, and their effect on enzyme activity.
Introduction
Enzymes are proteins known as biological catalysts.
In chemistry, a catalyst is a substance that speeds up a chemical reaction but is not consumed in the
reaction.
However, since this is not chemistry, we call them enzymes instead. We also call them enzymes because
they are inside your body.
Activation Energy
Enzymes speed up chemical reactions by lowering the energy of activation.
The energy of activation (aka activation energy) is the amount of energy needed
to get a reaction going.
In simple terms, imagine that you need to climb a very steep mountain. The
amount of energy that you need to go over the mountain is the energy of
activation. Now, imagine having a good friend called “enzyme.” Your friend,
enzyme, has the ability of lowering the mountain-top. Thus, you will now go over
the mountain without having to sweat about it.
This mountain is so
high! Please enzyme,
bring it down!
Activation Energy
Pg. 59
Enzyme Naming
Enzymes are specific to the reaction that they catalyze (speed up). Therefore,
their names have something to do with the reaction that they catalyze.
Lactase, for example, is the enzyme that breaks down the sugar in milk, lactose.
Lactase only works for this type of reaction. Other reactions need their own
specialized enzymes.
Amylase is another type of enzyme that is present in human saliva. It is in charge
of breaking down starch into simple sugars.
Notice that both lactase and amylase end with the suffix –ase. This is true for the
majority of enzymes. If you see the “-ase” ending, then it is an enzyme.
Keep in mind that every rule has an exception. Not all enzymes end in –ase.
Pepsin is an enzyme found in your stomach that does not end in –ase.
Trypsin is an enzyme found in your small intestines that does not end in –ase.
Enzymatic Activity
Enzymes attach themselves to a substance called the substrate.
The enzyme and the substrate combine in a way similar to a lock-and-key.
This is called the enzyme-substrate complex. There is a slight change in
enzyme shape as it attaches to the substrate. This slight enzymatic change is
known as an induced fit.
Only a part of the enzyme called the active site catalyzes a reaction. By the
way, the fancy words catalyzes, catalysis, catalyst, etc…just mean speed up a
chemical reaction.
The substrate will bind to the enzyme’s active site to perform catalysis.
Factors Affecting Reaction Rates
Many things can affect enzymatic activity, but we will focus on three things: temperature, pH, and the
amount of enzyme or substrate.
Enzymes happen to work best at certain temperatures. For example, the enzymes in your body work
best at 37°C or 98.6°F. This is called the optimal temperature for these particular enzymes found in your
body. It is the temperature where these enzymes are working at their best (optimum). If you have a very
high fever, the enzymes will speed up, but then they may stop working.
Pg. 60
Heat increases enzymatic activity. But too much heat denatures the enzymes (looses 3D shape).
On the other hand, cooling an enzyme may simply put the enzyme in a “sleep-like” state (inactive).
Enzymes also work better under optimal pH
concentrations. Remember that pH is a measurement
of the acid/base. The enzyme pepsin, found in your
stomach, has an optimal pH of about 1 or 2. Pepsin
may not work if the pH increases to become basic.
When an enzyme is outside its temperature and pH
range, it may lose its 3-dimensional protein shape
and become denatured.
Normally, a reaction will speed up if there are more enzymes to get
the job done. The converse is also true (less enzymes = slower
reaction).
Sometimes reaction rates can increase when you add substrates to a
reaction because it becomes easier for an enzyme to attach itself to
the substrate since there are so many of them. Thus, adding more
substrates may increase the reaction rate. However, if you continue
adding more substrates, the enzyme will come to a point where it
cannot work any faster, and the reaction continues at a steady speed.
Pg. 61
Energy
SC.912.L.18.10
Connect the role of adenosine triphosphate (ATP) to energy transfers within a cell.
SC.912.P.10.1
Differentiate among the various forms of energy and recognize that they can be transformed from one form to
others.
Introduction
The first law of thermodynamics states that the energy in the universe cannot be created nor
destroyed. Energy in the universe is constant.
The second law of thermodynamics is the law of entropy. Entropy is a fancy
word for disorder. A system tends to want to be in disorder. For example, an ice
cube placed on a kitchen top could represent a system. Eventually the ice-cube
begins to melt causing a mess in your kitchen.
This disorder, or entropy, is a result of heat being released. Every chemical
reaction produces some heat that is lost to the surrounding.
Energy is constantly changing forms. For example, plants harvest the energy
from sunlight and transfer it to chemical energy found within sugars. Then,
an animal, such as a cow, may eat the plant and gather its chemical energy.
Finally, the cow is able to transform the chemical energy from the plant into
mechanical energy, which allows the cow to move around. In addition, the
cow will release heat to the environment.
ATP
ATP stands for adenosine triphosphate.
ATP is a high energy molecule composed of a ribose sugar, an
adenine base, and three high energy phosphate groups.
The energy in ATP is found in the bonds that connect each
phosphate. Energy is released when a phosphate is broken off.
ATP – 1 phosphate = ADP (adenosine diphosphate)
ADP – 1 phosphate = AMP (adenosine monophosphate)
(Most Energy)
ATP …………ADP…………AMP
(Least Energy)
ATP is the energy currency of the cell. Cell’s use ATP to carry out all biological
process, such as breathing, movement, talking, etc…
Pg. 62
Photosynthesis
SC.912.L.18.7
Identify the reactants, products, and basic functions of photosynthesis.
Introduction
Photosynthesis is a process by which plants, green algae, cyanobacteria, and some protists use to
convert sunlight into chemical energy.
For this biology class we will focus on plant photosynthesis only.
6CO2 + 6H2O + sunlight  C6H12O6 + O2
(memorize this formula)
carbon dioxide + water + sunlight  sugar + oxygen
Photosynthesis mainly occurs in the leaves of plants in an organelle called the
chloroplast. Inside the chloroplast is a special pigment called chlorophyll. Pigments absorb light.
Chlorophyll is capable of absorbing red, violet, and blue. Chlorophyll,
however, cannot absorb green! Whatever is not absorbed will be
reflected. This is why plants are mainly green because green is
reflected onto your eyes.
There are two reactions that occur during photosynthesis:
light-dependent reaction and light-independent reaction.
The light-dependent reaction of photosynthesis occurs within the
chloroplast in disk-like structures called thylakoids.
The light-independent reaction of photosynthesis (sometimes called
the dark reaction) occurs within the chloroplast’s jelly-like substance
called the stroma.
Pg. 63
The general concept of photosynthesis begins in
the thylakoids. (Light-dependent reaction)
*Water and light enter the thylakoids. The light
splits the water into oxygen gas, which is
released as a byproduct, and ATP & NADPH are
formed.
Light-dependent
Light-independent
The second part of photosynthesis will now
continue in the stroma (Light-independent
reaction)
*The ATP and NADPH made in the lightdependent reaction are used in conjunction with
carbon dioxide to power the Calvin cycle.
* Once the Calvin cycle is powered, sugars are
made. Since the energy in ATP and NADPH has
been used, these molecules are recycled as ADP
and NADP+.
Do not confuse the words stroma and stoma
The Light-dependent Reaction: Photoysystem II and Photosystem I
The light-dependent reaction occurs in the thylakoids of the chloroplast and is made possible by a
machinery of pigments and proteins called photosystem II and photosystem I. Notice that photosystem
II occurs first.
The products of the light-dependent reaction are oxygen, ATP, and NADPH.
PS II
Light and water enter the thylakoids within the photosystem II machinery. The light is absorbed by a
special chlorophyll pigment which absorbs light at 680 nanometers. We call this pigment P680.
The light splits the water, which causes the release of oxygen. This process also produces hydrogen ions
(H+ ions) and high energy electrons.
The high energy electrons are then passed down an electron transport
chain to produce energy in the form of ATP. As electrons pass down the
electron transport chain, hydrogen ions are pulled into the thylakoids
space. The high concentration of H+ ions is then forced out of an
enzyme called ATP synthase. When H+ ions pass through the ATP
synthase, energy is formed by combining a phosphate group to ADP to
produce ATP. This process of going from ADP to ATP with the help of
light is called Photophosphorylation.
Pg. 64
PS I
By the time the electrons from photosystem II reach photosystem I, they have very little energy. A
second light source must re-charge these electrons when they reach photosystem I. The pigment that
absorbs light in photosystem I is called P700 because it absorbs light at 700 nanometers.
The electrons are now energized and ready to pass a second and shorter electron transport chain. The
electrons are picked up by NADP+ in the stroma, along with H+. This produces the final product of the
light-dependent reaction, NADPH.
Please LOOK at the picture below and try to see what is happening as you read the information above
The Light-independent Reaction: The Calvin cycle
The light-independent reaction is sometimes called the dark reaction
or the Calvin cycle. We do not call it the dark reaction anymore
because it is misleading. It does not need to be dark for it to happen.
During the light-independent reaction, ATP, NADPH, and carbon
dioxide are used to make high-energy sugars.
Pg. 65
The Calvin cycle: C3 Pathway
Carbon dioxide enters the Calvin cycle and mixes with a sugar called
Bisphosphate (RuBP). This occurs because of the enzyme
(Ribulose Bisphosphate Carboxylase).
The first organic compound to be formed in the Calvin cycle
is PGA, a 3 carbon molecule.
PGA is then energized by ATP and NADPH to produce a
higher-energy molecular state called PGAL or G3P.
Since G3P is the first product made, and it contains 3
carbons, this form of photosynthesis is called the C3
pathway. Many plants undergo the C3 pathway.
Notice that glucose is NOT the first sugar made. The first
sugar made is G3P, which is later turned into a variety of
sugars, such as glucose, sucrose, etc.
Photorespiration
Plants close their stomata when it is too hot in order to conserve water. Therefore,
carbon dioxide is not able to enter the plant, and the oxygen made is stuck in the
plant. This is not good news.
At this point, the plant’s enzyme, RuBisCo, will bind to the oxygen. This method
does not produce any energy at all (it actually wastes energy).
No sugars are produced either.
In summary, photorespiration is bad for plants. It takes their energy and does not
really do anything good for plants.
Evolutionarily speaking, some plants have adapted ways to deal with intense light,
high temperatures, and low carbon dioxide levels.
Ribulose
RuBisCo
Pg. 66
C4 Pathway
The C4 pathway occurs in plants that are under intense light, high temperatures, and low carbon
dioxide.
The C4 pathway requires extra energy in the form of ATP, and it is
common in corn, sugarcane, and sorghum.
The C4 pathway uses two cells to perform photosynthesis:
Mesophyll cell and Bundle-sheath cell.
Carbon dioxide and PEP combine thanks to the enzyme PEP
carboxylase to form a 4 carbon molecule called Oxaloacetate. The
Oxaloacetate is later converted to another 4 carbon molecule
called Malate. This all happens in the Mesophyll cell. Because
Malate is a 4 carbon molecule, we call this the C4 pathway.
The Malate is then transferred to the bundle-sheath cell where it is
broken down into carbon dioxide and pyruvate. The carbon
dioxide is used to power the Calvin cycle while pyruvate is recycled
back to the Mesophyll cell to later be turned back into PEP.
Crassulacean Acid Metabolism (CAM) Photosynthesis
CAM plants are similar to C4 plants because they are adapted to very
hot and dry environments.
Examples of CAM plants include pineapple trees and many desert
cacti.
CAM plants allow air to go in only at night when they open their
stomata. At night, carbon dioxide is combined with organic acids and
stored in the plant. During the day when the
stomata are closed, these acids release the
carbon dioxide into the Calvin cycle to
produce carbohydrates.
Pg. 67
Cellular Respiration
SC.912.L.18.8
Identify the reactants, products, and basic functions of aerobic and anaerobic cellular respiration.
SC.912.L.18.6
Discuss the role of anaerobic respiration in living things and in human society
Introduction
All organisms get energy from food. The energy in food is expressed in a unit called the calorie.
Cellular respiration is the process by which energy is released from food in the presence of oxygen.
C6H12O6 + O2  6CO2 + 6H2O + ATP (memorize this formula)
sugar + oxygen  carbon dioxide + water + energy
Notice that the formula for cellular respiration is the same as photosynthesis but backwards. Also notice
that the energy in photosynthesis is solar while in cellular respiration it is chemical energy.
Cellular respiration can occur aerobically (with oxygen) or anaerobically (without oxygen).
The process of glycolysis is always first and is present in aerobic and anaerobic respiration.
OXYGEN
Glycolysis
No
OXYGEN
Fermentation
Krebs cycle (citric acid cycle)
Lactic Acid
Fermentation
Electron Transport chain
&
Oxidative phosphorylation
Alcoholic
Fermentation
Pg. 68
Aerobic Respiration (with oxygen)
If oxygen is present, cellular respiration will begin with glycolysis, form an intermediate called acetyl
CoA, enter the Krebs cycle, and finish with the electron transport chain and oxidative phosphorylation.
Technically speaking, glycolysis does not need oxygen to function, so it is anaerobic. Memorize this. It is
usually asked on all tests.
Glycolysis occurs in the cytoplasm of cells where 1 molecule of glucose is broken down into pyruvic acid
(aka pyruvate), ATP, and NADH.
Notice that in photosynthesis we dealt with NADPH and NADP+, but in cellular respiration we deal with
NADH and NAD+.
After glycolysis, the pyruvic acid is converted into acetyl CoA, which then enters the Krebs cycle.
The Krebs cycle takes place in
the matrix of the
mitochondria of eukaryotic
cells.
Acetyl CoA mixes with
Oxaloacetate to produce
citric acid (aka citrate). Since
citric acid is the first product,
we also call the Krebs cycle
the citric acid cycle.
The Krebs cycle produces
very little energy, some
carbon
dioxide (which you breathe
out), and a lot of electron
carriers
(NADH, FADH2) which will later be used to make a lot of energy.
The electron carries NADH and FADH2 are ready to dump
their electrons onto the inner membrane of the mitochondria called
the cristae. This is where the electron transport chain is found.
The electrons that are dumped on the electron transport chain are
passed on from protein to protein. As this is happening, the
intermembrane space of the mitochondria becomes filled with hydrogen
ions. These hydrogen ions are then forced to go back
into the matrix through the enzyme ATP synthase. Energy (ATP) is produced
in the process when ADP is attached to a phosphate. This is called phosphorylation. Since
Pg. 69
oxygen is the final electron acceptor in the chain, we specifically call this step oxidative
phosphorylation.
The electron transport chain and oxidative phosphorylation together produce the most amount of
energy (about 36 molecules of ATP from 1 sugar in eukaryotes).
Notice how the
electrons force the H+
to go to the
intermembrane space.
Then notice how the H+
is forced back into the
matrix of the
mitochondria by the
“red” enzyme ATP
synthase. This produces
ATP.
Keep in mind that while not all organisms perform photosynthesis, ALL organisms perform cellular
respiration, including plants (ALL ORGANISMS)
One last thing to note is that while eukaryotes perform cellular respiration in their mitochondria,
bacterial cells do not contain mitochondria! So how do they do cellular respiration? They perform the
same functions in their cell membrane.
Anaerobic Respiration (without oxygen)
What happens where there is no oxygen?
Glycolysis will continue to run, since it is an anaerobic process. It will produce the same products,
pyruvic acid, energy, and NADH. Unfortunately, we cannot have all this high energy NADH running
around, so we need something to bring it back to its lower
energy state, NAD+.
In alcoholic fermentation, the products of glycolysis are turned
into an alcohol called ethanol, carbon dioxide, and NAD+ (look
we managed to bring that high energy NADH back down to
NAD+). Unfortunately, no ATP is produced =( ….but at least we
get alcohol and bread =)
By the way, humans cannot do alcoholic fermentation. This is
done by the fungus yeast.
Pg. 70
In lactic acid fermentation, the products of glycolysis are turned into lactic acid and NAD+ (look we
managed to bring that high energy NADH back down to NAD+). The lactic acid may cause muscle
soreness after you exercise. More fascinating though, bacteria use lactic acid fermentation to produce
cheese, yogurt, buttermilk, and sour-cream. COOL!
Comparing photosynthesis and cellular respiration
SC.912.L.18.9
Explain the interrelated nature of photosynthesis and cellular respiration.
Photosynthesis Equation:
6CO2 + 6H2O + sunlight  C6H12O6 + O2
Notice that these are the same equations but in
reverse to each other.
Cellular Respiration Equation:
C6H12O6 + O2  6CO2 + 6H2O + ATP
In photosynthesis we have solar energy while in
respiration we have chemical energy (ATP)
Photosynthesis removes carbon dioxide from the environment
while cellular respiration puts it back in the environment.
Keep in mind that animals cannot do photosynthesis. Only
plants, some bacteria, and some protists can perform
photosynthesis.
Also, keep in mind that ALL organisms can perform cellular
respiration. Plants are fortunate because they can do both
photosynthesis and respiration.
Some factors affect the rate of photosynthesis. These factors
include light intensity, temperature, and water. If photosynthesis is affected, so will cellular respiration.
For the most part, high light intensity and temperature increases photosynthesis (and thus respiration).
The reverse is also true. Low light and low temperatures stop photosynthesis (and thus respiration).
One last thing, fungi cannot perform photosynthesis! I know these little guys look like plants but they
are not plants. Fungi are decomposers; they are Heterotrophs (consumers not producers).
Pg. 71
Cell Growth
SC.912.L.16.8
Explain the relationship between mutation, cell cycle, and uncontrolled cell growth potentially resulting in cancer.
Cell Cycle
-Cells grow and divide. This is what we call the cell cycle.
-The cell cycle is divided in two parts called interphase and
mitosis.
-Interphase deals with growth, and mitosis deals with cell
division.
-Interphase is further divided into 3 parts: G1, S, and G2
G1 = cell grows
S = DNA is replicated (aka copied)
G2 = more cell growth & organelle replication
Keep in mind that not all cells grow and divide. Neurons and muscle cells do not grow or divide. We
refer to their special state as G0.
Liver cells are also in G0 just like neurons and muscles, but liver cells have the ability to re-enter the cell
cycle and divide when they are needed.
Check-Points
-Cells undergo check points throughout several stages of the cell
cycle. If the cell does not pass the check-point, it is programmed to
kill itself.
-The cell suicide process is called apoptosis (this kind of suicide is
good…otherwise you get cancer)
-Check-points prevent DNA errors that may have serious consequences on
individuals.
Pg. 72
Cancer
-Cancer is uncontrolled cell growth that spreads to other parts of the body (metastasis).
-If the cell’s DNA becomes damaged and changed, we say that there is a DNA mutation.
-These mutations, or genetic mistakes, begin to accumulate. If the problem is not solved, the cells may
become cancerous.
-These mutations may cause cells to grow
uncontrollably, disregarding check-points and the
apoptotic (cell suicide) process.
-As cells continue to grow and divide, they begin to
clump up and form masses of cells called tumors.
-If the cells within the tumor stay in place and do not
spread to other parts of the body, the tumor is called
a benign tumor. Benign tumors are not cancerous.
- If the cells within the tumor spread to other parts of
the body, the tumor is said to be malignant (evil).
Malignant tumors are cancerous.
-Fun fact: a fancy word for “spread” is “metastasis.”
Malignant tumors have the ability to metastasize to
other parts of the body.
Fun fact: watch out for the suffix “-oma,” which is
indicative of a tumor (examples: carcinoma,
melanoma, sarcoma, glioma, etc)
Cancer Treatment
Surgery is used if the tumor is localized and easy to remove (benign
tumors). Sometimes doctors avoid surgery, because there is a risk that
this may cause the cancer cells to spread during the operation.
Radiation therapy uses high energy radiation to kill cancer cells. Sometimes
a laser beam is fired directly at a tumor to kill or shrink cancerous cells.
Chemotherapy involves injecting patients intravenously with chemicals that
target cells in the body that multiply quickly. Since cancer cells multiply
quickly, they will most likely die. Keep in mind that hair cells also multiply
quickly, so they will die too. This is why people’s hair fall off during
chemotherapy.
Pg. 73
Mitosis
SC.912.L.16.14
Describe the cell cycle, including the process of mitosis. Explain the role of mitosis in the formation of new cells
and its importance in maintaining chromosome number during asexual reproduction.
SC.912.L.16.15:
Compare and contrast binary fission and mitotic cell division.
Mitosis
Mitosis is nuclear division, by definition; however, most people think of mitosis as cell division.
-The goal of mitosis is to produce two identical daughter cells.
-Mitosis produces diploid cells.
-Mitosis only produces somatic cells (body cells). It does NOT produce gametes (sex cells).
-Mitosis can be divided into 4 phases: prophase, metaphase, anaphase, and telophase.
These stages occur continuously, but we separate them into phases to identify them during a test and to
better explain what is occurring. *Remember PMAT.
In prophase, the DNA prepares itself for the mitotic journey by coiling up into
chromosomes. The centrosomes begin to move to opposite poles of the cells.
*Remember that when you move to a new home, you pack things into boxes so
that nothing gets lost & so it is easier for you to carry. The cells do the same
thing. They pack their messy DNA into organized chromosomes.
In metaphase, the sister chromatids meet in the middle of the cell. The nucleus is no
longer present at this point and the Centrosomes are on opposite ends of the cell
In anaphase, the sister chromatids are torn apart. They Centrosomes release spindle fibers
that pull the chromatids apart and to opposite poles of the cell.
Pg. 74
In telophase, everything comes back together. The nucleus and nucleolus reforms, and the chromosomes become loose DNA again. At this point the two
daughter cells are about to split in half.
During Telophase of mitosis, cytokinesis occurs. Cytokinesis is the process by
which the cell’s cytoplasm splits and two identical daughter cells are formed.
In animal cells, a cleavage furrow is formed during cytokinesis. This cleavage
will eventually cause the two cells to split and become two
independent cells.
In plant cells, a cell plate forms between the two plant cells. This cell plate
eventually becomes the cell wall. Notice how the plant cells are stuck to each
other.
Importance of Mitosis
Mitosis is important because it allows somatic cells to regenerate. Somatic means body, so all cells in
your body are somatic, with the exception of sperm and egg cells, which are called sex cells.
Human somatic cells contain 46 chromosomes. In order to create two identical cells, these 46
chromosomes must duplicate during the S-phase of Interphase to become 92 chromosomes. Then, the
cell can divide in half so that each new cell acquires 46 chromosomes.
46
92
Parent Cell
S – phase (Interphase)
Chromosomes
Chromosomes
Parent Cell
46
Mitosis
Chromosomes
46
Chromosomes
Daughter Cells
Pg. 75
It is important to maintain the chromosome number. If the chromosome number changes, some disease
or abnormality may result. In humans, the chromosome number is 46. Therefore, all somatic cells MUST
have 46 chromosomes.
Binary Fission vs. Mitosis
-Remember that mitosis by definition is nuclear
division. Bacteria, however, do not have nuclei.
Therefore, bacteria do not undergo mitosis.
-Bacteria replicate through a process called
binary fission (literally: to cut in half).
During binary fission, bacteria replicate their
circular DNA, send them to opposite poles of
the cell, and the bacteria cut themselves in half.
-There is no prophase, metaphase, anaphase, or
telophase in binary fission because these
are phases of mitosis.
Meiosis
SC.912.L.16.16
Describe the process of meiosis, including independent assortment and crossing over. Explain how reduction
division results in the formation of haploid gametes or spores.
Meiosis
-Meiosis produces 4 non-identical sex cells known as gametes.
-Meiosis occurs in two divisions, which are called Meiosis I and Meiosis II.
-Meiosis produces haploid cells.
-In males, meiosis only occurs in the testes to produce sperm cells. The sperm cell is the male gamete.
-In females, meiosis only occurs in the ovaries to produce egg cells. The egg cell or ovum is the female
gamete.
*Before we continue into meiosis, it is important to understand some chromosome terminology.
Human Chromosomes are pieces of linear DNA that have been wrapped and condensed to make the
process of cell division occur smoothly without losing any information.
Remember that humans have a total of 46 chromosomes (23 from dad and 23 from mom). At the end of
meiosis, each sperm or egg cell will be left with only 23 chromosomes.
When DNA undergoes the S-phase of Interphase, the 46 human
chromosomes make exact copies that result in 92 chromosomes.
Each identical copy of the chromosome is called a sister chromatid.
Pg. 76
The sister chromatids will be joined together like Siamese twins at a center location called the
centromere.
Moreover, for every chromosome you receive from your mom, you will receive a similar chromosome
from your dad. These similar chromosomes are called homologous chromosomes.
At the end of mitosis or meiosis, the sister chromatids split to become an individual chromatid or
chromosome.
Meiosis I
-Meiosis I is divided into prophase I, metaphase I, anaphase I, and telophase I.
-2 non-identical daughter cells will be produced in meiosis I.
Prophase I is probably the most important and complicated phase of meiosis I. It is
highly tested on exams. In prophase I, a mom chromosome will pair with a dad
chromosome. The pairing only occurs for homologous chromosomes, which are those
chromosomes from mom and dad that are similar (same size, same genes, etc). The
pairing of these homologous chromosomes is called synapsis. Furthermore, because
you can see a total of 4 sister chromatids in this homologous pairing, we call them
tetrads.
Now, the most important thing will take happen. A piece of the mom chromosome will
flip with a piece of the dad chromosome. They exchange genetic information. As a
result, this is one reason why everyone on this planet looks different. Imagine all the
combination of genes that take place during this random crossing over of genetic
information.
In Metaphase I, the homologous chromosomes align themselves randomly in the middle
of the cell, known as the metaphase plate. They will then be randomly separated during
anaphase. This random separation of chromosomes and genes is known as independent
assortment, and it is the second reason why everyone in the world is different.
*Pay attention to this. In metaphase I, the tetrads align in the middle, while in metaphase
II the sister chromatids align in the middle.
Pg. 77
In anaphase I, the homologous chromosomes, or tetrads, are randomly pulled apart to
opposite poles of the cell.
*Pay attention to this. In anaphase I, the tetrads are separated, while in anaphase II the sister
chromatids are separated.
In Telophase I and cytokinesis, two daughter cells are produced. Each daughter cell has now
46 chromosomes (instead of 92), and they will each undergo a second division in meiosis II
to produce a total of 4 daughter cells with 23 chromosomes each.
Meiosis II
-Meiosis II is divided into prophase II, metaphase II, anaphase II, and telophase II.
-A total of 4 non-identical cells will be seen at the end of meiosis II.
Prophase II is not as interesting as prophase I. Prophase II is actually quite simple and boring. The
only thing that happens in prophase II is that the nucleus breaks down and the DNA becomes
chromosomes.
In metaphase II, the sister chromatids align in the metaphase plate.
*Remember that in metaphase I the tetrads, or homologous chromosomes,
aligned in the middle.
Pg. 78
In anaphase II, the sister chromatids are pulled to opposite poles of the cell.
*Remember that in anaphase I the tetrads, or homologous chromosomes, were pulled
apart.
In Telophase II and cytokinesis, these two non-identical daughter cells split to become 4 nonidentical daughter cells with 23 chromosomes each. These are called sex cells, or gametes.
*Remember that in Telophase I we produced 2 non-identical daughter cells with
46 chromosomes each.
Mitosis vs. Meiosis
SC.912.L.16.17
Compare and contrast mitosis and meiosis and relate to the processes of sexual and asexual reproduction and their
consequences for genetic variation.
Comparison Graph
# of cells produced
Takes place
Diploid vs. Haploid
Reproduction
Chromosome Count
# of divisions
Type of cell produced
Examples of cells
Mitosis
2
Everywhere except testes & ovaries
Diploid
Asexual
46
1
Somatic cells (body cells)
Skin cells, hair cells, liver cells, etc
Meiosis
4
Testes and Ovaries
Haploid
Sexual
23
2
Sex cells (gametes)
Sperm and egg cells only
-A diploid cell contains both sets of chromosomes. One set is from mom and the other set is from dad. The human
diploid count is 46.
-A haploid cell contains half the set of chromosomes. The human haploid count is 23. Sperm and egg are haploid
cells because they each contain 23 chromosomes.
Pg. 79
Human Karyotype
-A human karyotype is a picture taken of the human chromosomes to
determine the sex: male or female.
-The homologous chromosomes are paired and placed in order from longest to
shortest.
- To determine the sex, look at the very last pair of chromosomes (pair #23). If
you see two chromosomes that are the same size, then we refer to the sex as
female. If you notice that one chromosome on the 23rd pair is much longer
than the other one, we refer to the sex as male.
- The female’s 23rd pair is XX, while the male is XY.
Many genetic disorders occur on the X chromosome. These diseases that
affect the sex chromosomes are known as sex-linked diseases.
Fortunately for females, they are usually not affected by these sex-linked
diseases because they have a back-up X chromosome in case one fails.
Remember women are XX.
Unfortunately for males, they are more prone to suffer from sex-linked
diseases since they only have one X chromosome and one Y. If the X
chromosome is damaged, then genetic diseases, such as Hemophilia, ALD, color blindness, and more are seen in
males. These diseases may also occur in females, but are less common.
Reproductive Systems
SC.912.L.16.13
Describe the basic anatomy and physiology of the human reproductive system. Describe the process of human
development from fertilization to birth and major changes that occur in each trimester of pregnancy.
Purpose of Reproduction
-The purpose of reproduction is to populate the world and to pass on one’s genetic information to the
next generation.
- Sexual reproduction leads to genetic variation.
-The main function of the male reproductive system is to make sperm cells.
-The main function of the female reproductive system is to make egg cells, or ova.
Pg. 80
Male Reproductive System
The journey of sperm cells:
1. Sperm cells are made in the testes. (The male hormone testosterone is also produced in the testes)
2. Sperm cells travel to the epididymis to grow and mature.
3. Sperm cells then travel up and around the vas deferens.
4. The vas deferens becomes the urethra and the sperm is bathed in a milky fluid known as seminal
fluid.
5. The prostate gland and seminal vesicle release the seminal fluid onto the sperm cells. This
combination of sperm and fluid is called semen.
6. The semen continues to travel down the urethra until it is released from the penis.
*It is important to note that the bladder, an organ that contains urine, is not part of the reproductive
system. It is actually part of the urinary system. Both, urine and semen travel through the urethra and
out of the penis.
The testes are located outside of the body in a sac called the scrotum. Sperm cells die when it gets too
hot, so the testes are outside the body where it tends to be a bit cooler for sperm cells to survive.
Female Reproductive System
The journey of egg cells:
1. Egg cells are made in the ovaries. (The female hormone Estrogen is also made in the ovaries)
2. Usually one egg cell is released every month from one of the ovaries. This process is called ovulation.
3. The egg cell will travel down the entire length of the fallopian tube (some books refer to the fallopian
tube as the oviduct or uterine tube)
4. The egg cell must be fertilized by a sperm cell while it is in the fallopian tube. If fertilization does not
take place during this time, the egg cell will die. This is a common test question: Where does fertilization
occur? In the fallopian tube
5. If the egg cell is fertilized, it will ultimately become a blastocyst. The blastocyst will implant itself on
the wall of the uterus to become an embryo and then a fetus.
Pg. 81
6. After about 9 months, the fetus is ready to be delivered. The cervix, which is the neck of the uterus,
will dilate so the fetus can move into the vagina, or birth canal.
7. The fetus then exits the female’s body through the vagina, or birth canal.
*It is important to note that babies DO NOT grow in the stomach!! Otherwise you would have a
barbecued baby. The baby grows and develops in the uterus.
Stomach
Uterus
Introduction to DNA and RNA
-DNA stands for deoxyribonucleic acid.
-RNA stands for ribonucleic acid.
-All nucleic acids (DNA and RNA) are composed of basic building blocks called nucleotides.
-DNA is double stranded (double helix/twisted ladder).
-RNA is single stranded.
-A nucleotide is composed of a sugar, a phosphate, and a nitrogenous base.
-The sugar in DNA is called deoxyribose.
-The sugar in RNA is called ribose.
-DNA contains 4 nitrogenous bases: A, T, C, G
-RNA contains 4 nitrogenous bases : A, U, C, G
Nucleotide
Pg. 82
Notice above that DNA and RNA share the bases A, C, and G. However, the base “T” is only found in DNA while
the base “U” is only found in RNA.
Nitrogenous bases
A = adenine
Purine
G = guanine
C = cytosine
U = uracil
Pyrimidine
T = thymine
-The purines are adenine and guanine. These are bases that have two rings.
-The pyrimidines are cytosine, uracil, and thymine. These bases have one ring.
*Mnemonic: pyramids cut. (Pyrimadines: cytosine, uracil, thymine)
-Purines will always attach themselves to pyrimidines.
- Adenine will always pair with thymine in DNA. A double hydrogen bond holds
them together.
-Guanine will always pair with cytosine in DNA. A triple hydrogen bond holds
them together.
In RNA, adenine will pair with uracil, since there is no thymine in RNA.
*So what is the difference between deoxyribose and ribose? Take a look below
Deoxyribose literally means, “a ribose without oxygen.”
Comparing DNA and RNA
Pg. 83
Nucleic Acid
Sugar
Bases
Strands
DNA
Deoxyribose
A, T, C, G
2 strands
RNA
Ribose
A, U, C, G
1 strand
The structure of DNA is anti-parallel. Notice above (picture on the right) that the pointy tip of the DNA
pentagon is pointing up on the left DNA strand, but on the right strand the pointy tip of the pentagon is
pointing down.
*Important: the sugars and phosphates make up the backbone of the DNA ladder, while the bases make
up the rungs (aka steps) of the ladder.
DNA History
British scientist Rosalind Franklin took an X-ray picture of DNA in 1952.
(X-ray Crystallography)
American biologist James Watson and British physicist Francis Crick used the X-ray picture from Rosalind
Franklin to finish their 3-dimensional model of DNA. Watson and Crick later received the Nobel Prize,
while Rosalind Franklin died and never won anything.
DNA Replication
SC.912.L.16.3
Describe the basic process of DNA replication and how it relates to the transmission and conservation of the genetic
information.
SC.912.L.15.15
Describe how mutation and genetic recombination increase genetic variation.
SC.912.L.16.4
Explain how mutations in the DNA sequence may or may not result in phenotypic change. Explain how mutations in
gametes may result in phenotypic changes in offspring.
Pg. 84
Introduction to DNA Replication
Cells must replicate their DNA before they divide. This occurs in the S-phase of Interphase.
DNA strands are complementary. This means that if you know one strand of DNA, you can draw its
second strand.
DNA strand: 3’– A T T A G C T C – 5’
Complementary Strands
DNA strand: 5’ – T A A T C G A G – 3’
*Notice that the strands are also anti-parallel. The 3’-end is
complementary to the 5’-end.
DNA replication is semi-conservative. This means that when
DNA replicates, it will contain one old strand and one new
strand.
The Process of DNA Replication
1. The enzyme helicase unwinds the double stranded DNA.
2. Single-Strand Binding Proteins (SSBs) attach to the DNA strands to prevent reannealing.
SSBs
3. Primase adds RNA primers to both strands of DNA.
Pg. 85
4. DNA polymerase searches for the RNA primers that were created by primase. DNA polymerase then
adds DNA nucleotides in a 5’  3’ direction. Because DNA polymerase can only add nucleotides in a 5’
 3’ direction, one strand will grow continously (leading strand) while the other strand will have to be
made in discontinously (lagging strand) in fragments called Okazaki fragments.
Lagging Strand
Leading Strand
5. The pieces of RNA must be removed from DNA. RNase H will remove the RNA primers from the DNA.
RNase H
DNA polymerase
RNA primer
6. Another DNA polymerase returns and fills in the Okazaki fragments from the removal of the RNA
primers.
Pg. 86
7. Finally, Ligase must link short strands of DNA. This completes the process of DNA replication.
Mutations in DNA
If I asked you to copy a book by hand, what are the chances that you will not make a mistake during the
copying process? Do think you can copy a book with extreme precision and detail, such that you will not
miss a comma, capital letter, or period?
The enzymes in charge of DNA replication sometimes make mistakes when they copy DNA. These
mistakes are called mutations.
Just one tiny mistake may ruin your life. Look below how one tiny change in a DNA base causes an
individual to develop a disease of the blood called sickle-cell anemia. That one tiny change caused the
amino acid valine to form instead of glutamic acid. The mutation shown below is an example of a
point mutation.
*Relax, although a lot of mutations are occuring in your body every single day, not all of them are
dangerous. In order for your future child to inherit one of these diseases, the mutation must occur in the
sex cells (sperm and egg) during meiosis.
Pg. 87
Types of Mutations
-As you saw in the picture above, sickle-cell anemia is an example of a point mutation.
-There are three types of point mutations: silent mutation, missense mutation, and nonsense mutation.
Point Mutations:
1. Silent mutation: This is a point mutation that
does not change the amino acid sequence in the
protein. It is silent because nothing really
happens.
2. Missense mutation: This point mutation
creates a brand new amino acid sequence in the
protein. Sickle cell anemia is an example of a
missense point mutation.
3. Nonsense mutation: This point mutation does
not code for any amino acid. It causes the amino
acid chain to stop.
*Notice in the picture above how the normal amino acid should be lysine (Lys). With a silent mutation,
the same amino acid (Lys) is still made even though there was a change in the DNA. With a nonsense
mutation, no amino acid is placed and the protein STOPS. Finally, with the missense mutation, a
different amino acid results.
The most dangerous types of mutations are those that cause the DNA frame to shift. These are called
frameshift mutations. Any addition or deletion of a base may cause the DNA frame to shift. Therefore,
additions and deletions may lead to frameshift mutations.
Point mutations are base-substitution mutations; they are NOT frameshift
mutations.
Notice the picture to the right. The deletion of the base “G” from “GAA”
causes a shift in the entire DNA sequence. This shift now contains the new
DNA information “AGG,” “CAC,” and “GT,” which will now create the
amino acids Lys and His, instead of the normal code of Glu, Ala, and Gly.
This is how a frameshift mutation looks like in an english sentence.
Normal: THE CAT AND THE MAN ARE FAT
Deletion of “T” in “THE”: HEC ATA NDT HEM ANA REF AT
Insertion of “A” (random letter): ATH ECA TAN DTH EMA NAR EFA T
Do you see why frameshift mutations are so bad!?
Pg. 88
Protein Synthesis
SC.912.L.16.5
Explain the basic processes of transcription and translation, and how they result in the expression of genes.
SC.912.L.16.9
Explain how and why the genetic code is universal and is common to almost all organisms.
Introduction to Protein Synthesis
Cells carry out life functions by making proteins. Everything in your body is protein with some
exceptions, such as your skeleton and teeth.
Central Dogma of Molecular Biology: DNA  RNA  Protein
Image all of us in a cooking school. DNA is our cook book and the chefs are called ribosomes.. It contains
all the recipes to make different kinds of foods, or proteins. (Ribosomes make proteins)
If we have 1 cook book called DNA, and we have 30 chefs, we need to do something so that each chef
has a copy of the recipe they are going to cook. Therefore, we make plenty of photocopies of the recipe,
which we call RNA.
There are 3 common types of RNA: mRNA, rRNA, and tRNA.
The photocopies that we just made with our “recipe” is called mRNA (messenger RNA) because it carries
the message, or the recipe. In eukaryotes, this message (mRNA) is carried out of the nucleus into the
cytoplasm.
The chefs, or ribosomes, need to grab that message (mRNA). The ribosome will read the message and
try to make a protein. Unfortunately, the ribosome doesn’t have any supplies to cook this recipe, so a
tRNA (transfer RNA) must transfer those supplies to the ribosome. Each tRNA will transfer 1 amino acid
to the ribosome. Remember that lots of amino acids add up to make a protein.
rRNA or ribosomal RNA is simply the RNA found within the ribosome. There is nothing special about this
kind of RNA. Think of it as the “uniform of the chef.”
When DNA is turned into RNA, the process is called
transcription.
When RNA is turned into protein, the process is called
translation.
Transcription
In eukaryotes, transcription takes place in the nucleus of
the cell. In transcription, the DNA will be “photocopied”
or “transcribed” into RNA (specifically mRNA).
*It is extremely important for the test that you know how to transcribe a piece of RNA from DNA. I will
provide you with a piece of DNA, and I am going to show you how to transcribe it. Look below
DNA strand: 3’– A T T A G C T C – 5’
DNA strand: 5’ – T A A T C G A G – 3’ (let’s use this DNA strand to create our mRNA template)
Pg. 89
mRNA: 3’ – A U U A G C U C – 5’ (Notice how we use “U” in RNA instead of “T”)
Finally, the mRNA that we just created needs to be edited. To finalize our mRNA, we need to remove a
piece of the mRNA called the intron. Remove all the introns. We are now done with transcription.
Translation
Translation is the process by which RNA is translated to protein, and it occurs in the cytoplasm for both
eukaryotes and prokaryotes.
In translation, a ribosome grabs on to the mRNA and begins to
read its message. Several tRNA, each carrying one amino acid, will
head toward the ribosome. The ribosome will grab on to the tRNA
based on the instructions from the mRNA.
The mRNA is read 3 letters at a time. These three letters is called a
codon. The first three letters, or first codon, in all proteins is the
start codon AUG. AUG codes for the amino acid methionine.
The ribosome must attach a tRNA with the anti-codon UAC to the
codon AUG on the mRNA. Look at the picture to the right 
Once the tRNA leaves its amino acid, the tRNA is discarded, or
thrown away. Remember, every tRNA brings only 1 amino acid.
Pg. 90
*On the exam, I will give you an mRNA strand and ask you to place the right amino acids according to
the strand. For example, notice the RNA picture above. GUG codes for Val. CAC codes for His. CUG codes
for Leu. Every three letters (codon) codes for 1 amino acid.
I have to memorize
every amino acid and
every 3 letter
code????
Eh, relax doc.
You don’t.
I will give you a
chart.
Use this chart to create your protein. Every three letters is
one amino acid.
mRNA: AUG – UAU – CGU – GUU – CUA – GGU – UAA
Protein: Met – Tyr – Arg – Val – Leu – Gly – Stop
You do not need to memorize the names of the amino
acids. You do not need to memorize that Met stands for
methionine, or Tyr stands for tyrosine, etc…
Mendelian Genetics
SC.912.L.16.1
Use Mendel’s laws of segregation and independent assortment to analyze patterns of inheritance.
SC.912.L.16.2
Discuss observed inheritance patterns caused by various modes of inheritance, including dominant, recessive,
codominant, sex-linked, polygenic, and multiple alleles.
SC.912.L.14.6
Explain the significance of genetic factors, environmental factors, and pathogenic agents to health from the
perspectives of both individual and public health.
Introduction to Heredity
Gregor Mendel is the father of heredity. He did hundreds of experiments on
pea plants. Unfortunately, he was not recognized for his work until years
after his death.
*Before we continue, let us go over the concept of a gene and an allele.
Let’s say we want to study eye color. Let “B” represent brown eyes and “b”
represent blue eyes.
Pg. 91
Remember that you have two parents (a mommy and a daddy), so you will get one letter from each
parent. You have three different mathematical possibilites: BB or Bb or bb
If you get BB, then you have brown eyes.
If you get bb, then you have blue eyes.
But what if you get Bb? Does this mean you have one brown and one blue eye? Absolutely NOT.
If you get Bb, then you have brown eyes. (I will explain why in a moment)
The two letters combined “BB”, “Bb”, and “bb” represent genes. Genes are segments of DNA that code
for a specific protein.
Each individual letter “B” or “b” is called an allele. Therefore, your mom gives you one allele and your
dad gives you the other allele.
BB= Gene
Bb = Gene
bb= Gene
B = allele
b =allele
Mendel’s Laws
1. Law of Dominance: The dominant allele will be expressed.
* Remember Bb = brown eyes. This occurs because brown is dominant to blue, so brown is physically
expressed while blue is hidden.
2. Law of Segregation: In meiosis (back when sperms and eggs were made), the alleles were segregated,
or separated. As a result, every sperm and egg is different. Then, each time a baby is formed, the baby
looks slightly different from his or her mom, dad, brother, sister, etc…
3. Law of Independent Assortment: Independent traits, such as eye color and hair color, assort
themselves indepdently. In other words, just because you have blue eyes does not mean you will
automatically have blue hair.
How did Mendel figure this out?
1. Gregor Mendel got a purple pea plant and self-fertilized it to create a pure breed (PP = purple).
2. Gregor Mendel got a white pea plant and self-fertilized it to create a pure breed (pp = white)
*Notice how we use “P” for purple and “p” for white. We keep the letters the same, but one letter is big
and one is small.
3. Gregor Mendel then did an experiment. He got his pure purple pea plant
and crossed fertilized it with his pure white flower. To his surprise, 100% of
the pea plants were purple! What happened to the white!? Did it dissapear?
Pg. 92
4. Mendel then got one purple pea plant that was produced from the purple and white parent pea
plants. He calls these purple pea plants the F1 Generation because they are the offspring of the parent
generation above.
5. When Mendel self-fertilized a purple pea plant from the F1 generation, he
got the following results: 75% purple and 25% white pea plants. The white did
not dissapear! It reappeared in this new generation, which he called the F2
generation.
The Punnett Square (Monohybrid Cross)
Scientists today use punnett squares to predict outcomes. A punnet square is a box (literally a square)
that we will used to determine probabilities.
Let’s use the following assumptions to create a punnet square:
Example 1:
1. Assume your mom has brown eyes and has the genotype BB. (the genotype, or genes are the two
letters)
2. Assume your dad has blue eyes and has the genotype bb.
3. Let’s create a punnett square to determine the probabilities that you or your siblings will come out
with brown or blue eyes.
b
b
Bb
Bb
Bb
Bb
B
B
If you notice from the punnett square above, all of the children of mom and dad have the genotype
“Bb.” This means that they all have brown eyes, since brown is dominant over blue. However since they
have a little “b,” they have the possibility of passing that “b” allele to the next generation.
Pg. 93
Example 2:
1. Assume your mom has brown eyes and has the genotype Bb.
2. Assume your dad has brown eyes and has the genotype Bb.
3. Let’s create a punnett square to determine the probabilities that you or your siblings will come out
with brown or blue eyes.
B
b
BB
Bb
Bb
bb
B
b
Notice how ¾, or 75%, of the children will have brown eyes. Notice how ¼ of the children, or 25%, will
have blue eyes.
*Since we are only studying one gene in this punnett square (eye color), we call this a monohybrid cross.
Genotype vs. Phenotype
As stated above, a genotype is the gene, or genetic make-up, of
an organism. In the examples above, the three genotypes for eye
color were “BB”, “Bb”, and “bb.” These genotypes were used to
describe brown and blue eyes color.
Phenotype is the physical manifestation of an organisms
genotype. For example, the physical manifestation of an
organism with the genotype “BB” is brown eyes. Therefore,
brown is the phenotype. The physical manifestation of an
organism with the genotype “bb” is blue eyes. Therefore, blue is
the phenotype.
Try this:
1. Look at your eyes in the mirror and tell me your genotype…………you can’t!
2. Now, look at your eyes in the mirror and tell me your phenotype…..do you have blue, brown green,
etc?
As you probably inferred, you can tell a person’s phenotype by simply looking at them, but you cannot
determine their genotype by simply looking at them.
Pg. 94
Homozygous and Heterozygous Genotypes
The genotype BB is homozygous dominant. (Also known as purebred)
The genotype bb is homozygous recessive. (Also known as purebred)
The genotype Bb is heterozygous. (Also known as hybrid)
*This is extremely important for the test. The math problems that you will solve on the test will use
these fancy words.
Test Example Question:
1. Alberto and Jennifer are thinking of having children and would like to know the probabilitie of having
a child with brown or blue eyes. Alberto has brown eyes and Jennifer has blue eyes. They go see a
geneticist to discuss these possibilities. The genetecist informs Alberto that he is heterozygous while
Jennifer is homozygous recessive. Figure out the possibilites that their children will have brown or blue
eyes by creating a punnett square.
2. Since Alberto has brown eyes, his genotype is either BB or Bb. If you continue reading, it says that
Alberto is heterozygous. This means that he must be Bb.
3. Jennifer has blue eyes. The passage above states that Jennifer is homozygous recessive. Jennifer must
then have the genotype bb. Even if the passage would not have said that Jennifer was homozygous
recessive, we still know that the genotype is bb because there is only one genotype for blue eyes, since
it is a recessive trait.
4. Create a punnett square and solve
B
b
BB
bb
Bb
bb
b
b
Notice that 2/4, or 50%, of the children will have brown eyes, and 2/4, or 50%, of the children will have
blue eyes.
Pg. 95
The Punnett Square (dihybrid Cross)
Sometimes we want to study two traits at the same time. In this example, the two traits we will study
are shape and color of seeds.
In terms of shape, round is dominant to wrinkled.
R = round
r = wrinkled
In terms of color, yellow is dominant to green.
Y = yellow
y = green
In this example we are going to make the following cross between two plants: RrYy x RrYy
Remember that “R & r” represent shape and “Y & y” represent color.
The first plant’s genotype is RrYy, so this plant has round seeds and yellow color. The second plant’s
genoptype is identical to the first plant. To solve this problem, we need to make a bigger punnett square
with 16 boxes, but how?
Let’s use a concept from math called FOIL:
RrYy  RY
Ry
rY
ry
(both plants in this example have the same genotype)
Test Cross
A test cross is a test used to determine if a dominant individual is homozygous or heterozygous.
Let’s use the example of widow’s peak, which is a dominant trait. If an individual has a
widow’s peak, he or she may be WW or Ww. So if you look at the picture to the right, is
Eddie from “The Munsters” homozygous (WW) or heterozygous (Ww)? You don’t really
know.
So the question is, how do we determine if Eddie Munster is homozygous (WW) or
heterozygous (Ww). The answer is, we need to have him marry and mate with a female
who does not have a widow’s peak (ww).
Let’s use Elena from “The Vampire Diaries” since she does not have a widow’s peak
and is therefore homozygous recessive (ww).
*Keep in mind that this is a probability, or a chance event.
-If all of the children have a widow’s peak, then Eddie Munster is more than likely WW.
Pg. 96
-If at least one of the children does NOT have a widow’s peak, then Eddie Munster is Ww.
- If you are in doubt, do a punnett square and you will see.
Single-Gene Traits and Polygenic-geneTraits
What do the following four features below have in common? They are all single-gene traits, which
means that they are all affected by only one gene. Single-gene traits are easy because you either have
them or you don’t. This allows us to create punnett squares. Single-gene traits can also determine if a
person is adopted or not.
On the other hand, polygenic-gene traits, are affected by two or more genes. Therefore, they are much
harder to be used to determine important information like whether someone is adopted or not.
Pg. 97
Beyond Mendelian Genetics: Incomplete Dominance, Codominance, & Sex-Linked
Traits
Some traits do not follow the laws that we learned from Gregor Mendel, especially the law of
dominance.
Incomplete dominance occurs when neither trait is dominant over the other. A
blend of the traits appears.
Codominance is when both alleles are expressed. Look at the Dalmatian to the right.
The Dalmation is NOT a blend of white and black. The Dalmation IS both white and
black.
The examples that will be used on test for codominance are based on blood types, so
learn this.
For codominant traits we use superscripts:
Blood Type A: IAIA or IAi
Blood Type B: IBIB or IBi
Blood Type AB: IAIB (blood type AB is the only blood type that is codominant)
Blood Type O: ii (notice that O-blood is recessive, and we use ii)
Blood types can also be used to determine if a person is adopted or not. Read at
the example below.
Pg. 98
The Charlie Chaplin case: In 1941, Charlie Chaplin became romantically involved with a young actress
named Joan Barry. In 1943, twenty months after the relationship ended, she had a child and claimed
Charlie Chaplin as the father. A paternity suit ensued. Chaplin had type O blood. Barry had type A
blood. The baby had type B blood. Was the baby Chaplin’s? (Yes or No) Provide written explanation
and/or charts to support your answer.
You are still
going to pay
child support!
LOSER =P
That’s not
my baby!
Blood Genotype: ii
Blood Genotype: IAIA or IAi
Draw a Punnett square and find out if Chaplin really is the baby’s daddy. Since Chaplin has blood type O,
which is recessive, use the alleles ii. Since Joan Barry is blood type A, she may have the genotype IAIA or
IAi. On the other hand, the baby is blood type B, which means that the baby’s genotype must be IBi, it
cannot be IBIB because we know the mother, Joan Barry, does not carry “B” alleles.
The conclusion:
The baby could not have been Chaplin’s, since the B allele carried from the baby did not come from its
mother and could not have come from Chaplin either. Three pathologists testified to this effect.
However, the jury was undeterred by the “scientific evidence” and ruled that Chaplin was the father,
ordering him to pay child support.
Sex-Linked Traits
Sex-linked traits are traits that are passed down to the child by the sex chromosomes (XX or XY).
Most sex-linked traits are carried on the X chromosome and most are
recessive traits. This means that for a female to have the disease, she
would need two defective X chromosomes. The male, however, only
needs one defective X chromosome to inherit the condition.
Hemophilia is a blood-clotting disorder carried on the X chromosome. It is
referred to as an X-linked recessive trait, since a female needs two
defective X chromosomes to inherit the disease.
Look at the example to the right, the mother is a carrier for hemophilia,
which means that she does not have the disease (XXh). The father does
have hemophilia since his only X chromosome is defective (XhY).
Pg. 99
Pedigrees
HE.912.C.1.4
Analyze how heredity and family history can impact personal health.
A pedigree is a picture representation of a family history.
Pedigrees help us determine the genotype of an organism.
Use the key below to understand how a pedigree works.
Most Important Pedigree Rules:
-Male = Square
-Female = Circle
-Shaded in = affected individual
-Roman Numeral = Generation
Autosomal Dominant Trait Characteristics:
1.
2.
3.
4.
Does not skip generation
Appears in both sexes with equal frequency
Both sexes can transmit the trait to the offspring
Affected persons have at least one affected parent
Autosomal Recessive Trait Characteristics:
1. Skips generations
2. Appears with equal frequency in both sexes
3. Affected offspring are usually born to unaffected parents.
4. Appears more frequent in children of consanguine marriages
Pg. 100
X-Linked Recessive Trait Characteristics:
(Highly tested on exams)
1. Appears more often in males
2. Not passed from father to son
3. Passed from mother to son
4. Women may have the disease, but the majority of women are
carriers
5. Hemophilia & color blindness are examples
X-Linked Dominant Trait Characteristics:
1. Appears in males and females, but they often appear more
in females. In fact, all females of affected parents will have it.
2. Does not skip generation
3. Affected men pass the trait to all their daughters but not
their sons
4. Affected women (if heterozygous) pass the trait on to about
½ of their sons and daughters.
Y-Linked Trait Characteristics
(Extremely unlikely to be tested on exams)
1. Only men have it
2. Trait is passed from father to son
3. Do not skip generations
4.Extremely rare
Pg. 101
Biotechnology
SC.912.L.16.12:
Describe how basic DNA technology (restriction digestion by endonucleases, gel electrophoresis, polymerase chain
reaction, ligation, and transformation) is used to construct recombinant DNA molecules (DNA cloning).
SC.912.L.16.10
Evaluate the impact of biotechnology on the individual, society and the environment, including medical and ethical
issues.
Introduction to Biotechnology
Biotechnology is the manipulation of living organisms or their parts to produce useful
products.
With biotechnology, we can do the following things and much more?
1. Paternity testing
2. Cloning of organisms
3. Crime investigation (Fingerprints/DNA analysis)
4. Genetically modifying fruits and vegetables to produce larger amounts of foods that
are also resistant to pests
5. Using bacteria to produce human hormones, like insulin, to treat diabetes
6. Finding of the cure of hundreds of diseases in the future like diabetes, cancer,
and HIV
7. Being able to modify a human genetically (imagine instead of plastic surgery,
genetic surgery; being able to change your eye color from brown to blue)
Dolly: First cloned
animal in the year 1996
Gel electrophoresis
-Gel electrophoresis is a technique that separes DNA, RNA, or proteins fragments
according to their size.
- Gel electrophoresis is commonly used in crime scenes to analyze the evidence
with the suspects’s DNA. This procedure may also be used to determine paternity.
For the test, you need to be able to read a gel electrophoresis.
Gel electrophoresis is very simple to read.
Compare the “Evidence” with all four suspects
shown on the picture to the left.
Notice that the “Evidence” matches with “Suspect 3”
This indicates that “Suspect 3” is probably guilty.
Pg. 102
Cloning
Cloning is the artificial production of a cell
or organism that is genetically identical to
the parent cell or organism.
Follow the steps in the picture on the right 
Recombinant DNA
Recombinant DNA is literally combining DNA from different
organisms.
Combining DNA is done in a field of science called genetic
engineering.
Viruses are used as vectors to insert the new DNA.
The hormone insulin is now made with the help of bacteria.
Therefore, we are able to manufacture insulin very efficiently
and at a low cost. (Highly tested on exams)
Restriction enzymes are like scissors. In this example, we use a
restriction enzyme to cut out the gene that codes for insulin in
humans. We then combine that human gene with a bacterial
circular chromosome called a plasmid. The plasmid is then
inserted in the bacterium. The bacterium is now capable of
producing human insulin.
In addition, we can use a technique called polymerase chain reaction (PCR) to make hundreds of copies of the
gene, in this case the insulin gene. These copies can then be transferred to many bacteria, and manufacturing insulin
has become easy and cheap in today’s world.
Pg. 103
Index
1
1st
B
Law of Thermodynamics · 8
A
abiotic factor · 10
Acid rain · 11
activation energy · 58
active immunity · 48
active site · 59
Active transport · 38
addition · 10, 61, 87, 102
adenine · 61, 82
adhesion · 25
aerobic · 67
AIDS · 50, 51
alcoholic fermentation · 69
Alfred Russell Wallace · 12
Algae · 9, 52
allele · 17, 19, 90, 91, 92, 98
alternation of generation · 57
amino acids · 16, 29, 30, 87, 88, 90
Amylase · 59
anaerobic · 67, 68
Analogous structures · 17
anaphase · 73, 75, 76, 77, 78
anaphase I · 76, 77, 78
anaphase II · 77, 78
angiosperms · 53, 54
Antibiotics · 48
antibodies · 30, 47, 48, 49, 51
Antifungals · 48
antigen · 47
anti-parallel · 83, 84
Antivirals · 48
Archbishop James Usher · 13
Arteries · 43
artificial selection · 15
Artificially Acquired Active Immunity · 48
Artificially Acquired Passive Immunity · 49
Atherosclerosis · 46
ATP · 10, 61, 63, 64, 65, 66, 67, 68, 69, 70
autotrophs · 9
bacteria · 9, 17, 21, 31, 34, 48, 55, 56, 70, 75, 101, 102
Bacteria · 9, 21, 31, 48, 75
Basophil · 47
B-cell · 47
behavioral isolation · 19, 20
benign tumor · 72
binary fission · 73, 75
Biogeography · 16
biomass · 8
Biotechnology · 101
biotic factor · 10
birth canal · 81
bladder · 80
blastocyst · 80
blood pressure · 43, 45, 46
Blood Type · 97
bottleneck effect · 18
brainstem · 42
bryophytes · 52
C
C4 · 66
Cancer · 72
candidiasis · 51
Capillaries · 43
Carbohydrates · 28
Carbon dioxide · 11, 65, 66
Carbon-14 · 21
carnivore · 9
Carolus Linnaeus · 22
Carpel · 53
carrying capacity · 11, 14
catalysts · 58
CD-4 · 20
cell membrane · 35, 36, 69
cell plate · 74
cellular respiration · 10, 35, 67, 68, 69, 70
cellulose · 28, 34, 55
centromere · 76
cerebrum · 42
CFCs · 11
Chaplin · 98
Pg. 104
Charles Darwin · 12, 13, 14
chemoautotrophs · 9
Chemotherapy · 72
chitin · 34
Chlorofluorocarbons · 11
chloroplast · 21, 32, 34, 62, 63
Chloroplasts · 36
clade · 23
cladograms · 23
cleavage furrow · 74
Cloning · 101, 102
Codominance · 97
codon · 89, 90
Cohesion · 25
Commensalism · 10
Comparative anatomy · 15
conjugation · 17
consumer · 9
consumers · 9, 70
coronary · 44
covalent bond · 24
crossing over · 75, 76
cytokinesis · 74, 77, 78
Cytokinesis · 74
Cytoplasm · 35
cytosine · 82
DNA · 16, 17, 20, 21, 23, 30, 35, 36, 50, 57, 71, 72, 73, 74,
75, 77, 81, 82, 83, 84, 85, 86, 87, 88, 91, 101, 102
dominant · 90, 91, 92, 94, 95, 97
E
Ecuador · 12
Egg · 80
embryo · 54, 80
Embryology · 15
Emu · 12
endosymbiotic theory · 21
energy · 8, 9, 10, 28, 29, 35, 36, 37, 38, 55, 58, 61, 62, 63,
64, 65, 66, 67, 68, 69, 70, 72
entropy · 61
Enzymes · 58, 59, 60
enzyme-substrate complex · 59
Eosinophil · 47
epididymis · 80
erythrocytes · 45
Estrogen · 80
eukaryotic · 21, 32, 36, 68
Everglades · 10
evolution · 12, 13, 14, 15, 16, 17, 19, 23, 53
F
D
Darwinian trees · 23
decomposer · 9
Decomposers · 9
dehydration synthesis · 30
deletion · 87
denatured · 60
density-dependent limiting factor · 11
density-independent limiting factor · 11
deoxyribonucleic acid · 81
Deoxyribose · 30, 82, 83
descent with modification · 12
detritivore · 9
diastolic · 45
Dicots · 54
dicotyledons · 54
Diffusion · 37
Diploid · 57, 78
directional selection · 18
disaccharide · 28
disruptive selection · 18
facilitated diffusion · 37
fallopian tube · 80
fertilization · 57, 79, 80
fetus · 80, 81
first law of thermodynamics · 61
first line of defense · 47
fossil record · 13, 15
founder effect · 19
frameshift mutations · 87
Francis Crick · 83
frequency · 17, 19, 99
Fungi · 9, 31, 34, 48, 70
G
G3P · 65
Galapagos Islands · 12
gamete · 75
gametophyte · 57
Gel electrophoresis · 101
gene pool · 17
Pg. 105
Genetic drift · 18
genetic engineering · 102
genotype · 18, 92, 93, 94, 95, 98, 99
Geographic isolation · 20
Glucose · 28
glycolysis · 67, 68, 69, 70
Glycolysis · 68, 69
Golgi Apparatus · 35
greenhouse · 10, 11
greenhouse effect · 10
Gregor Mendel · 90, 91, 97
guanine · 82
guard cells · 55
gymnosperms · 53
H
H.M.S. Beagle · 12
half-life · 21
haploid · 57, 75, 78
Hardy-Weinberg Equilibrium · 19
Hardy-Weinberg Principle · 19
Harold Urey · 22
heart · 40, 43, 44, 45, 46
heat capacity · 26
helicase · 84
helper T-cell · 47
Helper T-cells · 20, 50
Hemophilia · 79, 98, 100
herbivore · 9
herbivory · 8
heterozygous · 94, 95, 100
HIV · 20, 48, 50, 51, 101
Homeostasis · 40
homologous chromosomes · 76, 77, 78, 79
Homologous Structures · 16
homozygous · 94, 95
Hornworts · 52
Hutton and Lyell · 13
hybrid · 94
hydrogen bonds · 24, 29
hydrolysis · 30
hydrophobic · 29, 36
hypertonic · 38
hypotonic · 38
I
Immunity · 48, 49
Incomplete dominance · 97
Index fossils · 20
Infections · 46
Inheritance of Acquired Characteristics · 13
insulin · 40, 101, 102
intermediate filaments · 32, 33
Intermediate filaments · 33
introns · 89
isotonic · 38
J
James Watson · 83
Jean-Baptiste Lamarck · 13
K
Kaposi’s sarcoma · 51
karyotype · 79
L
Lactase · 59
lactic acid fermentation · 70
lagging strand · 85
Lateral gene transfer · 17
Law of conservation of matter · 8
Law of Dominance · 91
Law of Independent Assortment · 91
Law of Segregation · 91
leading strand · 85
Ligase · 86
light-dependent reaction · 62, 63, 64
light-independent reaction · 62, 64
Lipids · 29, 36
Liverworts · 52
Lymphocyte · 47, 50
Lysogenic Cycle · 50
Lysosomes · 35
Lytic Cycle · 50
M
macromolecule · 28
macrophage · 47
Malignant tumors · 72
Meiosis · 75, 76, 77, 78
Pg. 106
meristems · 56
mesophyll · 55
metaphase · 73, 75, 76, 77
Metaphase I · 76
metaphase II · 76, 77
metastasis · 72
microfilaments · 32, 33
Microfilaments · 33
microtubules · 32, 33
Microtubules · 32
Missense mutation · 87
mitochondria · 21, 68, 69
Mitochondria · 35
Mitosis · 73, 74, 75, 78
Molecular Biology · 16, 88
Monocots · 54
monocotyledons · 54
Monocyte · 47
monosaccharide · 28
Mosses · 52
mRNA · 88, 89, 90
mutations · 14, 16, 19, 20, 72, 83, 86, 87
Mutations · 17, 86, 87
Mutualism · 10
N
natural selection · 12, 14, 15, 17, 19
Natural selection · 14, 15, 18
Negative feedback · 40
Neutrophil · 47
nitrogenous bases · 81
node · 23
Nonsense mutation · 87
Nucleic acids · 30
Nucleolus · 35
Nucleus · 31, 35
O
Okazaki fragments · 85
omnivore · 9
opportunistic infections · 51
organelles · 21, 34, 35
Osmosis · 37
Ostrich · 12
ovaries · 75, 78, 80
oviduct · 80
ovulation · 80
ozone layer · 11
P
Parasitism · 10
passive immunity · 49
passive transport · 37, 38
PCP · 51
PCR · 102
pedigree · 99
Penicillin · 48
penis · 80
Pepsin · 59, 60
peptidoglycan · 34
PGA · 65
PGAL · 65
pH · 11, 27, 58, 59, 60
Phagocytosis · 38
phenotype · 18, 93
Phenotype · 93
phloem · 55
phospholipid bilayer · 36
photoautotrophs · 9
photorespiration · 65
photosynthesis · 9, 10, 36, 55, 62, 63, 65, 66, 67, 68, 69, 70
Photosynthesis · 9, 10, 62, 66, 70
photosystem · 63, 64
phylogenetic trees · 23
Phylogeny · 23
Phytoplankton · 9
Pinocytosis · 38
Pistil · 53
plasma membrane · 36, 37, 38
Plasma Membrane · 31, 35
Platelets · 45
Pneumocystis Jirovecii Pneumonia · 51
point mutation · 86, 87
Polar · 36
Polygenic traits · 18
polygenic-gene traits · 96
polymerase · 85, 101, 102
polysaccharide · 29, 55
Population Density · 11
positive feedback · 40
power · 27, 31, 63, 66
predator · 8
prey · 8
Primary succession · 10
Primase · 84
Producers · 9
Pg. 107
prokaryotic · 21, 36
prophase · 73, 75, 76, 77
Prophase I · 76
Prophase II · 77
prostate · 80
protein coat · 20, 50
Proteins · 29, 84
protists · 21, 52, 62, 70
punnett squares · 92, 96
purebred · 94
Purines · 82
Pyrimadines · 82
pyruvic acid · 68, 69
R
Radiation therapy · 72
Radiometric dating · 21
Receptor-Mediated Endocytosis · 38
recessive · 90, 94, 95, 97, 98
Recombinant · 102
recombination · 17, 83
Red blood cells · 45
Relative dating · 20
Reproductive isolation · 19
Restriction enzymes · 102
Rhea · 12
ribonucleic acid · 81
Ribose · 30, 83
Ribosome · 31, 35
RNA · 20, 30, 35, 50, 81, 82, 83, 84, 85, 88, 89, 90, 101
RNase H · 85
Robert Hooke · 31
Rosalind Franklin · 83
Rough Endoplasmic Reticulum · 35
rRNA · 35, 88
RuBisCo · 65
RuBP · 65
S
saturated · 29
Scanning Electron Microscope · 32
scrotum · 80
second law of thermodynamics · 61
second line of defense · 47
Secondary succession · 10
semen · 51, 80
seminal vesicle · 80
sex-linked · 79, 90, 98
Silent mutation · 87
simple diffusion · 37
single-gene traits · 18, 96
Single-gene traits · 96
sister chromatid · 75
Smooth Endoplasmic Reticulum · 35
sodium-potassium pump · 38
solute · 25
solvent · 25
speciation · 19
Sperm · 32, 78, 80
sporophyte · 57
SSBs · 84
stabilizing selection · 18
stamen · 53
Stanley Miller · 22
stroma · 62, 63, 64
sun · 8, 9
surface tension · 26
Surgery · 72
synapsis · 76
systolic · 45
T
Taxonomy · 22
telophase · 73, 74, 75, 76, 77
Telophase I · 77, 78
Telophase II · 78
Temporal isolation · 20
test cross · 95
testes · 75, 78, 80
testosterone · 80
tetrads · 76, 77, 78
third line of defense · 47
Thomas Malthus · 14
thymine · 82
total magnification · 31
tracheophytes · 52, 53
transcription · 88, 89
translation · 88, 89
Transmission Electron Microscope · 32
tRNA · 88, 89
Trypsin · 59
tumor · 72
Pg. 108
U
W
unsaturated · 29
uracil · 82
use and disuses · 13
uterine tube · 80
Watson and Crick · 83
White blood cells · 45, 47
V
X-ray Crystallography · 83
xylem · 55
vaccine · 49
Vacuoles · 36
vagina · 81
vas deferens · 80
Veins · 43
Vestigial structures · 16
viscosity · 46
X
Z
Zooplankton · 9