Biology 2nd Semester Exam Review – Spring 2014
(B3F) Research and describe the history of biology and contributions of scientists.
Darwin – developed theory of evolution based on natural selection
Jenner – used first vaccine (used cowpox to prevent smallpox)
Fleming – discovered penicillin (first antibiotic)
(B4C) Compare the structures of viruses to cells, describe viral reproduction, and describe the role of viruses
in causing disease.
Describe the components of a virus. Nucleic acid, proteins (capsid, protein coat, surface proteins)
Why are viruses NOT considered cells? Don’t carry out cellular functions: growth, development, energy
utilization, protein synthesis, reproduction
How do the lytic cycle and lysogenic cycle differ? Lytic cycle causes cell death; lysogenic cycle includes viral
DNA in cell DNA but doesn’t kill the cell
How is HIV transmitted? Sexual contact, blood contact, mother to child
(B5B) Examine specialized cells, including roots, stems, and leaves of plants; and animal cells such as blood,
muscle, and epithelium.
Define meristematic tissue – plant tissue found in tips of roots and shoots; responsible for growth
Why do muscle cells contain more mitochondria than cells in other types of tissue? – high rate of cellular
respiration in muscle cells
(B5C) Describe the roles of DNA, ribonucleic acid (RNA), and environmental factors in cell differentiation.
Cells containing identical DNA aren’t necessarily identical. Why not? Not every gene is transcribed in every
cell. Cells transcribe the genes they need.
What does RNA allow the cell to do? Protein synthesis (takes information from DNA out to be “used”)
What does DNA do for the cell? Stores genetic information
(B6B) Recognize that components that make up the genetic code are common to all organisms.
What are the components of the genetic code? DNA (A-T-C-G), RNA (A-U-C-G) , amino acids
Which of these is a true statement? Explain why the false ones are false.
All organisms make the protein hemoglobin.
Not all organisms synthesis hemoglobin
All organisms contain DNA in a nucleus.
Not all organisms have a nucleus (prokaryotes)
All organisms synthesize proteins from genes.
All organisms are made of differentiated cells. Many organisms are unicellular, and not all multicellular organisms have
cellular differentiation
(B6C) Explain the purpose and process of transcription and translation using models of DNA and RNA.
Describe what is happening in the diagram above. RNA is being
transcribed from a section of DNA.
Use the codon chart to determine the amino acid sequence that
would be created from the portion of mRNA shown here.
mRNA: A U G A C G U C A U G C
Met – Thr – Ser - Cys
(B6D) Recognize that gene expression is a regulated process.
What is a gene? Segment of DNA that codes for a particular
protein
Describe conditions that would cause some genes to be
expressed and others not to be expressed.
-Environmental (depends on what is available in the organism’s
environment)
-Internal (depends on what the organism needs to maintain homeostasis)
What component of DNA ultimately determines the traits of an organism? Sequence of nitrogen bases
B.6 (E) Identify and illustrate changes in DNA and evaluate the significance of these changes.
What is nondisjunction and what can happen as a result? Uneven separation of homologous chromosomes
during meiosis
What are the possible effects of a gene mutation? Change the production of a protein, make a new protein,
no change
What kind of gene mutations may be passed on to offspring? Mutations in gametes
What is a frameshift and what can happen as a result? Addition or deletion of one nucleotide base; changes
the base sequence; changes the protein
(B6H) Describe how techniques such as DNA fingerprinting, genetic modifications, and chromosomal
analysis are used to study the genomes of organisms.
What is gene therapy? DNA (for a particular gene) from an outside source is incorporated into a patient’s DNA
to treat disease
What is karyotype analysis? Technique that allows individual chromosomes to be seen via microscope
How is DNA fingerprinting used? Can be used to identify individuals (shows similarities among DNA samples)
(B7A) Analyze and evaluate how evidence of common ancestry among groups is provided by the fossil
record, biogeography, and homologies, including anatomical, molecular, and developmental.
Define:
Vestigial structure – serves no useful purpose in an organism; relic from earlier evolutionary form
Homologous structure – different mature forms in different organisms, but develop from the same
embryonic tissue
Analogous structure – similar function and similar appearance (due to convergent evolution), but of
different origin
Convergent evolution – process by which unrelated organisms independently evolve similarities when
adapting to similar environments
Coevolution – process by which two species evolve in response to changes in each other
Explain how each of the following provides evidence of common ancestry.
Fossil record – fossils can be used to show evolutionary change over time
Biogeography – geographic distribution of organisms on the planet follows patterns that are best
explained by evolution in conjunction with the movement of tectonic plates over geological time.
Homology of DNA and body structures – Related organisms share similarities that are derived from
common ancestors. Similarity on the molecular level shows that life has a common ancestor.
Development of different body structure shows evolutionary relationships.
(B7B) Analyze and evaluate scientific explanations concerning any data of sudden appearance, stasis, and
sequential nature of groups in the fossil record.
Use relative dating to describe the age relationships of the fossils shown.
Fossils at the top are youngest and fossils at the bottom are oldest. Fossils
found in the same layer are approximately the same age.
Why might a similar feature (such as a dorsal fin in sharks and dolphins) appear independently in organisms?
Fill a similar niche in a similar habitat (sharks and dolphins are both marine predators)
What is another name for such a feature? Analogous structure
(B7C) analyze and evaluate how natural selection produces change in populations, not individuals.
Define natural selection: process by which individuals that are better suited to their environment survive and
reproduce most successfully; also called survival of the fittest
Draw graphs for and explain directional, stabilizing, and disruptive selection.
Describe how the evolution of one species can affect the evolution of another. (Predator/prey)
Coevolution – smart, fast lions can catch antelope and survive; smart, fast antelope can escape and survive.
This means lions and antelope both get smarter and faster over time.
(B7D) Analyze and evaluate how the elements of natural selection, including inherited variation, the
potential of a population to produce more offspring than can survive, and a finite supply of environmental
resources, result in differential reproductive success.
Some species hundreds (or more) offspring at a time and others produce only a few offspring in their entire
lifetime. What is the advantage of these two different reproductive strategies? Producing many offspring
means that most can die – as long as a few survive the population will survive. Producing very few offspring
means that they are easier to care for and benefit from parental care.
How does life span relate to number of offspring produced at a time? (Generally speaking) More offspring at a
time = shorter life; fewer offspring at a time = longer life
(B7E) Analyze and evaluate the relationship of natural selection to adaptation and to the development of
diversity in and among species.
Define:
Adaptation – inherited characteristic that increases an organism’s chance of survival
Geographical isolation – form of reproductive isolation in which two populations are separated
physically by geographic barriers such as rivers, mountains, or stretches of water
Behavioral isolation – form of reproductive isolation in which two populations have differences in
courtship rituals or other types of behavior that prevent them from interbreeding
Why is diversity important? A diverse population has a higher chance at survival because the genetic variation
means that members of the population are likely to be able to survive a variety of conditions.
(B7F) Analyze and evaluate the effects of other evolutionary mechanisms, including genetic drift, gene flow,
mutation, and recombination.
Explain how each influences evolution:
Genetic drift – random change in allelic frequencies that occurs in small populations
Gene flow – (migration) any movement of genes out of one population into another
Mutation – source of new genetic material
(B7G) Analyze and evaluate scientific explanations concerning the complexity of the cell.
What is the endosymbiotic theory? Explains the origin of eukaryotic cells: Eukaryotic cells formed from a
symbiosis among several different prokaryotic organisms.
What characteristics of mitochondria and chloroplasts help support the endosymbiotic theory? Mitochondria
and chloroplasts reproduce like bacteria, have DNA more like bacterial DNA, and contain their own ribosomes.
(B8A) Define taxonomy and recognize the importance of a standardized taxonomic system to the scientific
community.
What goal does taxonomy accomplish? Taxonomy is the discipline of classifying organisms and assigning each
organism a universally accepted name. The goal is a common system that can be used and understood by all.
Why is binomial nomenclature important? Binomial nomenclature is a classification system in which each
species is assigned a two-part scientific name. It is important because there are often differences in regional
names and it ensures that people know the specific organism that is in question. (puma, mountain lion)
(B8B) Categorize organisms using a hierarchical classification system based on similarities and differences
shared among groups.
Create the following:
Simple Dichotomous Key
Simple Cladogram
(B8C) Compare characteristics of taxonomic groups, including archaea, bacteria, protists, fungi, plants, and
animals.
Fill in the following table using the following taxonomic categories: Archaea, Bacteria, Protists, Fungi, Plants,
and Animals. There will be some empty boxes.
Multicellular
Unicellular
Prokaryotic
Eukaryotic
Absorbtive
Ingestive
Heterotroph Heterotroph
Autotroph
Chitin
in cell
wall
Cuticle
Protists
Fungi
Plants
Animals
Archaea
Bacteria
Protists
Fungi
Archaea
Bacteria
Protists
Fungi
Plants
Animals
Archaea
Bacteria
Protists
Fungi
Archaea
Bacteria
Protists
Plants
Fungi
Plants
Protists
Animals
(B10A) Describe the interactions that occur among systems that perform the functions of regulation,
nutrient absorption, reproduction, and defense from injury or illness in animals.
How does the circulatory system work with the immune system during an immune response? The circulatory
system delivers phagocytes (nonspecific inflammatory response) and antibodies (specific defense.)
How does the digestive system work with the circulatory system to provide the body with nutrients? Small
intestine absorbs nutrients, which are absorbed into capillaries in villi and carried by blood vessels.
How does the excretory system work with the respiratory system to remove toxins from the body? Toxins
inhaled by the respiratory system may be passed on to the blood. Blood filters through the kidneys, which
remove the toxin.
How does the skeletal system help the respiratory and nervous systems? The skeletal system helps the
respiratory and nervous systems by protecting vital organs (lungs, brain, spinal chord.)
(B10B) Describe the interactions that occur among systems that perform the functions of transport,
reproduction, and response in plants.
What does vascular tissue do for plants? Transports water, minerals, and carbohydrates
How are nonvascular plants able to get what they need without xylem and phloem? Must get water and
minerals directly by osmosis and diffusion. Carbohydrates are stored/used where they are made, not
transported to other places within the plant.
What are stomata and what do they do? Openings (usually on the underside) of a leaf that allow carbon
dioxide and oxygen to diffuse into and out of the leaf.
What is a fruit? Thick wall of tissue surrounding an angiosperm seed (forms after fertilization)
Define and give examples of:
Gravitropism (geotropism) – response to gravity; roots grow down
Phototropism – response to light; stem bends toward light
(B11A) Describe the role of internal feedback mechanisms in the maintenance of homeostasis.
Define homeostasis: process by which organisms maintain a relatively stable internal environment
(steady state)
(B11B) Investigate and analyze how organisms, populations, and communities respond to external factors.
Describe how each responds to external factors:
Organism – physical, anatomical, behavioral
Population – grow, shrink, stay the same
Community – succession (change in community structure)
(B11C) Summarize the role of microorganisms in both maintaining and disrupting the health of both
organisms and ecosystems.
What is the major role of bacteria that enables them to maintain the health of organisms and ecosystems?
Decomposers
Describe a way in which a microorganism can (1) disrupt the health of an organism and (2) disrupt the health
of an ecosystem. (not necessarily the same microorganism) Certain microorganisms can cause disease and
even death, which impacts an individual (bacteria cause strep throat, protists cause malaria.) High
concentrations of marine microorganisms can cause algal blooms, which can cause widespread damage to
ecosystems.
(B11D) Describe how events and processes that occur during ecological succession can change populations
and species diversity.
Describe the two types of succession (starting conditions, pioneer species)
Primary – starts with bare rock (after volcano, glacier movement); lichen is first to grow .
Secondary – starts with soil (after fire, human disturbance); grasses are first to grow.
Describe a climax community. A climax community has reached a level of stability at the end of ecological
succession. Climax communities typically have high diversity, efficient nutrient and energy use, stable
population sizes, and include species with long life spans.
(B12A) Interpret relationships, including predation, parasitism, commensalism, mutualism, and competition
among organisms.
Provide examples of:
Predation – lion and antelope
Competition – European starling (introduced bird) and Tree swallow (native bird)
Parasitism – tapeworm  and human 
Mutualism – clownfish  and sea anemone 
Commensalism – cattle egret  and water buffalo –
(B12B) Compare variations and adaptations of organisms in different ecosystems.
Name the ecosystem (biome) in which the following adaptations would be best suited and explain why.
Extensive shallow roots – desert; quickly absorb rainfall
Dark colored, short wings adapted to high humidity and temperature – tropical forest; dark colors
blend well and short wings navigate easily in dense forest. Tropical forest has high humidity and temperature.
Needle-shaped leaves on downward sloping branches – Boreal forest; evergreen trees (have needles)
slope downwards so snow cannot accumulate.
Broad, flat-topped teeth and digestive systems especially adapted to feed on grasses – Grassland
(prairie); adaptations for grasses will be most beneficial where grass is the predominant food supply
(B12C) Analyze the flow of
matter and energy through
trophic levels using various
models, including food chains,
food webs, and ecological
pyramids.
Label each organism on the food
web using the terms producer,
primary consumer, secondary
consumer, tertiary consumer,
herbivore, carnivore, omnivore.
Some terms may be used more than
once.
Draw an energy pyramid and
explain what happens to energy
as it travels through a food chain.
Energy decreases as it moves up
through the food chain. Only 10%
of energy from one level moves up
to the next.
(B12D) Recognize that long-term survival of species is dependent on changing resource bases that are
limited.
What are limiting factors? What does a growth curve look like if there are none?
Limiting factors limit the growth of a population (food, water, predators, disease,
natural disasters, weather, climate.) A population without limiting factors
experiences exponential growth.
J curve →
Define carrying capacity. Carrying capacity is the maximum number of
individuals in a population that can be supported by the resources of a particular
area (ecosystem.)
Draw a logistic growth curve and label the carrying capacity.
S curve →
(B12E) Describe the flow of matter through the carbon and nitrogen cycles and explain the consequences of
disrupting these cycles.
Name three key features of the Carbon Cycle and three key features of the Nitrogen Cycle.
Carbon Cycle:
Nitrogen Cycle:
1. living things need/use carbon (in all biomolecules) 1. living things need/use nitrogen for DNA and proteins
2. photosynthesis/respiration
2. bacteria play a key role
3. present in atmosphere (CO2), biosphere 3. Plants get nitrogen from the soil, animals get it
(living things), and lithosphere (ground)
from plants
(B12F) Describe how environmental change can impact ecosystem stability.
What kinds of characteristics are found in a stable ecosystem? Stable ecosystems have high diversity, efficient
nutrient and energy use, stable population sizes, and include species with long life spans. (= climax
community)
Provide an example of an environmental change that can impact ecosystem stability. Natural disaster, human
disturbance