BIOLOGY
KEYSTONE REVIEW
TEST TAKING STRATEGIES

Read the question, pick out KEY TERMS
 There may be different forms of terms you are
familiar with
 Example: Homeostatic Mechanism
 Homeostasis = Ability to maintain
equilibrium
 Mechanism = How something is done
 So…Homeostatic Mechanism = The way
an organism maintains equilibrium. An
example would be shivering when cold
TEST TAKING STRATEGIES

“Attack” the question by breaking it down




Determine what the question is asking you to
explain/answer
Use caution – look for words like ALWAYS,
EXCEPT, NOT TRUE
Read ALL choices for a multiple choice before
selecting an answer
Use “process of elimination” for multiple choice to
narrow down your choices
TEST TAKING STRATEGIES


For essay/writing questions, tell the person what
you KNOW, they will not assume what you
mean.
For essay/writing questions, use definitions when
possible.

SPELL CORRECTLY

Answer ALL questions. Blank = NO CREDIT

Double check answers with any extra time you
have
BASIC BIOLOGICAL PRINCIPLES
Keystone BIO.A.1
PROKARYOTIC CELLS VS. EUKARYOTIC
CELLS
Eukaryotic Cell
Prokaryotic Cell
Nucleus:
Present
Absent
Number of
chromosomes:
One—circular; may
contain plasmids= small
More than one-linear circular DNA which often
gives bacteria resistance to
antibiotics
Cell Type:
Multicellular
Unicellular
True Membrane
bound Nucleus:
Present
Absent
Example:
Animals and Plants
Bacteria and Archaea
PROKARYOTIC CELLS

Bacteria:
LEVELS OF ORGANIZATION
Cells to Organism
LEVELS OF ORGANIZATION
ORGANIZATION - CELLS
Cells are the basic unit of life.
 All organisms (living things) are made of cells.


Unicellular – Can be Prokaryotic or Eukaryotic
Made of one cell
 Ex:
bacteria, protists, fungi (yeast)


Multicellular – Eukaryotic only
Made of many cells
 Ex: animals, plants, fungi

CELL TYPES AND ORGANELLES:
ANIMAL CELL = EUKARYOTIC
CELL TYPES AND ORGANELLES:
PLANT CELL = EUKARYOTIC
SUMMARY OF ORGANELLES (IN EUKARYOTES)
ORGANELLE
FUNCTION
MITOCHONDRION
Powerhouse of cell; makes ATP
RIBOSOME
Proteins made here
NUCLEUS
Houses DNA
NUCLEOLUS
Makes ribosomes
ENDOPLASMIC RETICULUM
Transport/ 2 types
(rough/smooth)
GOLGI BODY
Packaging
CHLOROPLAST
Glucose production
Site of photosynthesis
CILIA / FLAGELLA: responsible for cell movement
THE CHEMICAL BASIS FOR LIFE
Keystone BIO.A.2
WATER AND ITS PROPERTIES
• Changes in external heat do not easily effect the
temperature of water
• Ex – Oceans do not freeze
• Frozen water is less dense that liquid water
• Ex – Lakes freeze on top, but not throughout
• Water molecules bond strongly to each other
• Water is the “universal solvent” – It is a polar molecule
and readily dissolves many substances
CARBON
Why is Carbon suited to form macromolecules:
Carbon is the second most abundant element in
living organisms

Carbon can share four electrons, therefore it can
bond to four additional atoms

Carbon establishes covalent bonds
(stable, high energy bonds)

CONDENSATION AND HYDROLYSIS REACTIONS
Water Removed
Examples:
Water Added
+H2O
KEY CELL COMPOUNDS – CARBON
MACROMOLECULES:
TYPE
DESCRIPTION/FUNCTION
PROTEIN
Made of amino acids
Most abundant
Structure, movement, chemical
reactions. Some are ENZYMES
CARBOHYDRATE
Includes sugars, starches,
cellulose (plant support)
Provides energy
LIPID
Includes waxes and oils
Do not dissolve in water
Energy storage
Cell membrane structure
NUCLEIC ACID
Includes DNA, RNA & ATP
Store hereditary information
Direct cell activities
ENZYME / CATALYST
Catalyst = Speeds up a reaction
 Enzyme = A type of catalyst

Found in biological systems
 Composed of proteins

ENZYME / CATALYST

Activation Energy (Ea)

Enzymes / Catalysts can be affected by:



Temperature
pH
Concentration
BIOENERGETICS
Keystone BIO.A.3
ATP
The energy “currency” of life
 It is the high-energy molecule that stores the energy
we need to do just about everything we do.
 It is present in the cytoplasm and nucleoplasm of
every cell

PHOTOSYNTHESIS
6CO2 + 6H2O +  6O2 + C6H12O6
 Carbon dioxide + water = oxygen + glucose
 Changes radiant energy from sun into
chemical energy in glucose
 Occurs in chloroplast & uses chlorophyll

PHOTOSYNTHESIS

Occurs in 2 steps:

Light dependent reaction
Energizes electrons in chlorophyll; makes ATP
 Splits water and releases oxygen


Light independent (dark) reaction
Also called Calvin cycle
 ATP used to form glucose

ENERGY TRANSFERS:

PHOTOSYNTHESIS
Light Dependent:
Light Independent:
MITOCHONDRIA:
• “Power House of the Cell”
• Generate most of the cell's supply of
adenosine triphosphate (ATP),
CELLULAR RESPIRATION (AEROBIC)
6O2 + C6H12O6  6H2O + 6CO2 + energy (ATP)
 Chemical Energy in glucose is changed to
Chemical Energy in ATP
 Occurs in 3 steps when oxygen is present:

GLYCOLYSIS


Splits glucose to produces 2 ATP
KREBS CYCLE

Glucose broken down farther to make additional ATP
through
ELECTRON TRANSPORT
RESPIRATION
Mitochondrion
Glycolysis
Electron
Transport
RESPIRATION (ANAEROBIC)
Oxygen is NOT present
 Glycolysis occurs (glucose is split)
 Following glycolysis- 2 choices


Alcoholic Fermentation


yeast
Lactic Acid Fermentation

Muscles in humans
HOMEOSTASIS AND TRANSPORT
Keystone BIO.A.4
HOMEOSTASIS
Maintenance of stable internal conditions
required for cells to survive
 CELL MEMBRANE (PLASMA MEMBRANE)
plays key role


Selective permeability
TRANSPORT ACROSS THE CELL MEMBRANE

Passive Transport






Includes diffusion
Includes facilitated diffusion
Does not require energy
Substances move from high to low concentration
With concentration gradient
Osmosis is diffusion of WATER across membrane
TRANSPORT ACROSS THE CELL MEMBRANE

Active transport
Requires energy (ATP)
 Substances move from LOW to high concentration
 Against concentration gradient
 Will include Pumps, Endocytosis and Exocytosis

MEMBRANE-BOUND ORGANELLES CAN
FACILITATE TRANSPORT:
COMPARISON OF TRANSPORT METHODS:

Active transport requires energy whereas passive
transport does not
Active transport involves the carrying of molecule
against or solute against a concentration
gradient
-Pumps, Endocytosis, Exocytosis
 Passive transport involves carrying of a molecule
along the concentration gradient


Diffusion, Osmosis, Facilitated Diffusion
CELL GROWTH AND
REPRODUCTION
Keystone BIO.B.1
CELL CYCLE
Division of
cytoplasm
Or MEIOSIS
Interphase =
G1, S and G2
CHROMATIDS
Ex - spinal, nerve
and brain cells.
MITOSIS
NUCLEAR DIVISION – SOMATIC/BODY CELLS
PHASE
DESCRIPTION
PROPHASE
Nuclear membrane dissolves
Spindle apparatus forms
METAPHASE
Chromatids align mid cell
ANAPHASE
Chromatids separate
Now are individual chromosomes
TELOPHASE
Nuclear membrane reforms
MEIOSIS
NUCLEAR DIVISION – SEX CELLS
Meiosis I
Stage
Description
Prophase I
Spindle fiber forms
Pairing of homologous
sets
Metaphase I
Align center of cell
Anaphase I
Homologous pairs split
Telophase I
2 new cells= ½ #
chromosomes with
copies
Meiosis II
Stage
Description
Prophase II
Spindle fiber forms
Metaphase II
Aligns mid cell
Anaphase II
Chromatids separate
Telophase II
Total 4 new cells
GENETIC INFORMATION
MITOSIS
MEIOSIS
Creates identical cells
Creates sex cells (gametes)
Exact same # of chromosomes
½ number of chromosomes
Diploid to diploid or haploid to
haploid
Diploid (2 sets of chromosomes)
to haploid (1 set of chromosomes)
No genetic variety
Creates genetic variety
GENETIC INFORMATION

DNA





GENE / ALLELE


Nucleic acid made of phosphate, sugar (deoxyribose),
and nitrogen bases (adenine, guanine, cytosine,
thymine)
Base pairing: A = T C = G
Basic building block: nucleotide
Stores the genetic code
Section of DNA which has
a code for one trait
CHROMOSOME
One molecule of DNA
 Humans have 46

PATTERNS OF INHERITANCE

DOMINANT & RECESSIVE GENES/ALLELES
Genes/Alleles occur in pairs
 The dominant gene is seen in the organism
 Recessive gene is masked


EXAMPLE:
R = gene/allele for right handedness
 r = gene/allele for left handedness
 In general:
 if you have a gene for both right handedness and left
handedness, you will be RIGHT HANDED

GENETICS

Punnett Squares:
Determines Genotype
 Used to predict probability of offspring having certain
characteristics/traits/phenotypes/appearance

(teachers – click to fill in answers)
R

Example:
Rr X
R
Rr
r
RR
Rr
r
Rr
rr
PATTERNS OF INHERITANCE

MULTIPLE ALLELES
Certain traits have more than 2 different forms
 Blood types occur from 3 different gene forms (alleles)

A
B
O
AB are co-dominant (dominant together )=
A and B are dominant over O
AA, AO =
BB, BO =
OO
=
Type O blood is the UNIVERSAL DONOR
type AB blood
type A
type B
type O
PATTERNS OF INHERITANCE

SEX LINKED TRAITS





Are carried on X chromosome
Sex chromosomes = X or Y
Females = XX
Males = XY
COLOR BLINDNESS,
HEMOPHILIA (blood clotting)
PATTERNS OF INHERITANCE
Incomplete Dominance
Ex: Red Flower + White Flower produces Pink Flowers

PATTERNS OF INHERITANCE

Polygenic (Many Genes)
Ex – Skin Color
CHANGES TO COMPOSITION AND NUMBER
OF CHROMOSOMES

Crossing over

Nondisjunction
o Duplication
CHANGES TO COMPOSITION AND NUMBER
OF CHROMOSOMES

Translocation

Deletion
CHANGES TO COMPOSITION AND NUMBER
OF CHROMOSOMES

Insertion

Inversion
GENETIC MUTATIONS
Nonsense mutations
A nucleotide mutation creates a codon that STOPS
the transcription process earlier than it should.

Silent mutations
A change in one base that still creates the amino
acid that was desired.

Frameshift Mutation
The addition of or the removal of a nucleotide
causes all following codons to be read incorrectly

PATTERNS OF CHANGE IN SYSTEMS

RENEWABLE RESOURCES



NONRENEWABLE RESOURCES



Cannot be replaced by natural processes as quickly
as they are used
Ex: coal, oil, natural gas, minerals
GENETICALLY ENGINEERED PRODUCTS


Can be replaced or renewed through natural
processes
Ex: air, soil, water, living things
Altering of genetic makeup to produce desired traits
ORGANIC FOOD PRODUCTION

Growing of crops or raising of livestock without use of
synthetic chemicals
GENETICS
Keystone BIO.B.2
RNA AND DNA
DNA
RNA
Stays in nucleus
Throughout cell
Sugar = deoxyribose
Sugar = ribose
Double stranded
Single stranded or globular
Adenine, guanine, cytosine,
thymine
Adenine, guanine, cytosine,
URACIL
3 TYPES OF RNA
messenger (mRNA)
transfer (tRNA)
ribosomal (rRNA)
nucleus to cytoplasm (ribosome)
cytoplasm to ribosome
makes up ribosomes/in nucleolus too
GENETIC INFORMATION

PROTEIN SYNTHESIS
Occurs in 2 steps
 TRANSCRIPTION & TRANSLATION

GENETIC INFORMATION

TRANSCRIPTION

Copying of DNA’s code in nucleus of cell by
messenger RNA
GENETIC INFORMATION

TRANSLATION
Reading of mRNA into a protein
 Every 3 bases on mRNA (CODON) – 1 amino acid
 tRNA (transfer RNA) retrieves amino acid from cell
 Carries to ribosome to be put into protein

PROTEIN PRODUCTION:
Ribosomes: They are responsible for assembling the
proteins of the cell.
Endoplasmic Reticulum: Manufacturing site for
proteins.
Golgi Apparatus: Packages proteins inside the cell
before they are sent to their destination
Nucleus: DNA is found in the nucleus, which is the
template for protein production.
GENETIC INFORMATION

REPLICATION
Occurs before a cell divides in 2
 Process in which DNA makes a copy of itself

CAN YOU…..

Complete the other half of the DNA molecule
below? (Teachers – give time to answer then click
to check!)

A - T - C -
G

T -
C -
A - G -
- G - C - A - T
C
- G - T - A
THEORY OF EVOLUTION
Keystone BIO.B.3
EVOLUTION

Who developed the theory?


What is EVOLUTION?


Charles Darwin during the 1800s
Organisms change over time
Why do organisms change?

Natural selection:
Organisms pass on traits through their genes/alleles
 All organisms have slightly different characteristics. If
these characteristics/adaptations help them survive in a
particular environment, they will pass the traits on to their
offspring- thus changing the characteristics and the allele
frequency of the population over time

EVOLUTION

EVIDENCE?
Fossils
 Similar body forms
 Similar embryos
 Similar DNA & amino acid sequences in proteins

FACTORS CONTRIBUTING TO NEW SPECIES:




1. Migration - the movement of genes into or out of a
population. This includes pollen or seeds blowing into
the population from a source that is otherwise
considered to be a separate population.
2. Genetic drift - some individuals may, just by chance,
leave behind a few more descendents (and genes, of
course!) than other individuals. The genes of the next
generation will be the genes of the “lucky” individuals,
not necessarily the healthier or “better” individuals.
3. Isolating Mechanisms - something (as a
geographical, ecological, physiological, anatomical, or
psychological barrier) that limits breeding between
groups.
4. Founder Effect – the gain of genetic variation that
occurs when a new population is established by a very
small number of individuals from a larger population.
GENETIC MUTATIONS

May create Genotypic and Phenotypic Variations
within a Population
SCIENTIFIC METHOD




A scientific theory is an explanation inferred from
multiple lines of evidence for some broad aspect of the
natural world and is logical, testable, and predictive.
As new evidence comes to light, or new
interpretations of existing data are proposed, theories
may be revised and even change; however, they are
not tenuous or speculative.
A scientific hypothesis is an inferred explanation of
an observation or research finding; while more
exploratory in nature than a theory, it is based on
existing scientific knowledge.
A scientific law is an expression of a mathematical or
descriptive relationship observed in nature.
ECOLOGY
Keystone BIO.B.4
LEVELS OF ORGANIZATION
BIOTIC AND ABIOTIC COMPONENTS OF
ECOSYSTEM


Biotic factors: all the living things in an
environment (i.e. bacteria, plants, insects, birds,
and other animals).
Abiotic: all the non-living things in an
environment (i.e. wind, precipitation,
temperature, current in a stream, soil, caves).
ENERGY TRANSFERS IN ECOSYSTEM
o
SUN is ultimate energy source on planet!
Food chains show the movement of energy through
an ecosystem.
Sun grass grasshopper mouse snakehawk

Grass
= producer (autotroph)
Grasshopper = primary consumer (herbivore)
Mouse
= secondary consumer (carnivore)
Snake/hawk = tertiary consumers
FOOD WEB – SHOWS OVERLAPPING FOOD
CHAINS
Organisms are INTERDEPENDENT
ENERGY PYRAMID
POPULATION DYNAMICS

POPULATION


Group of organisms in same species @ same location
POPULATION DENSITY

How crowded area is: # individuals /unit area
LIMITING FACTORS:


Weather, flood, fire

Resource limitations: food, space, shelter, nesting
These can lead to population decline or species
elimination
BIOTIC INTERACTIONS OF ECOSYSTEMS



Symbiosis - When two (or more) species live and
interact closely together
Competition - Happens when 2 (or more) organisms
both try to use the same limited resource
Predation - When one organism (the predator)
captures and kills another organism (the prey) for
food
HUMAN AND NATURAL DISTURBANCES
LEAD TO:

ECOLOGICAL SUCCESSION
Communities replaced by newer communities due to
a change in an area
 PRIMARY

Occurs in area where no community exists
 Can follow a disaster (volcanic eruption/earthquake)


SECONDARY
Soil intact
Existing community cleared by disturbance (ex: farming)

PIONEER SPECIES

First organisms to inhabit ecosystem
RECYCLING OF MATTER
NITROGEN
CYCLE
RECYCLING OF MATTER
CARBON
CYCLE
RECYCLING OF MATTER
Water Cycle:
RECYCLING OF MATTER
OXYGEN CYCLE