Download ECA Review ANSWER KEY

NORTH CENTRAL HIGH SCHOOL
CP & X Biology
End of Course Assessment
(E.C.A.) Review
Revised 4/16/14, Chelsea Parsey
North Central High School
Standard 1: Cellular Chemistry
Core Standard
Describe the basic molecular structure and function of the four major categories of organic compounds
(carbohydrates, lipids, proteins and nucleic acids) essential to cellular function.
Core Standard
Describe how work done in cells is performed by a variety of organic molecules, especially proteins, whose
functions depend on the sequence of their monomers and the consequent shape of the molecule.
The “Big Idea”
Terms to KNOW & USE
B.1.1 Describe the structure of the major categories of
organic compounds essential to living organisms in terms of
their building blocks and the small number of chemical
elements (carbon, hydrogen, nitrogen, oxygen, phosphorous,
and sulfur) from which they are composed.
Monomer, polymer, organic, inorganic, atom,
element, molecule, compound, macromolecule,
monosaccharide, polysaccharide, amino acid,
protein, fatty acid, lipids, nucleotide, nucleic acids
1. Identify the six main elements found in a living organism.
CARBON
HYDROGEN
NITROGEN
OXYGEN
PHOSPHOROUS
SULFUR
2. There are four categories of organic molecules in living organisms. Fill-in the blanks in the following
chart.
ESSENTIAL
MONOMERS
POLYMERS
FUNCTION
NAME ID
COMPOUND
MONOSACCHARIDE
POLYSACCHARIDE
Energy
Most end in –ose
Carbohydrates
FATTY ACIDS
Phospholipids
Triglycerides
Waxes
Cell Membranes
Energy Storage
Insulation
Most monomers
end with –ic and
are acids
AMINO ACIDS
Polypeptides
Structures
(muscle, bone,
hair, etc.)
Enzymes
Many end in –ase
NUCLEOTIDES
DNA
RNA
Store and
Transmit genetic
information
The “NA” in DNA
& RNA stands for
Nucleic Acid
Lipids
Proteins
Nucleic Acids
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The “Big Idea”
Terms to KNOW & USE
B.1.2 Understand that the shape of a molecule
Cell energy, enzymes, induced fit model,
determines its role in the many different types of cellular substrate, active site, DNA, RNA, cell transport,
processes including metabolism, homeostasis, growth
homeostasis, metabolism, chemical reactions
and development, and heredity, and recognize that the
majority of these processes involve proteins that act as
enzymes.
3. Explain what enzymes are and describe how they function.
Enzymes are biological catalysts that help to make chemical reactions in organisms happen
quicker. Enzymes use the INDUCED FIT MODEL, in which substance called a SUBSTRATE fits
into the ACTIVE SITE of an enzyme. The enzyme then produces PRODUCTS by either forming
or breaking chemical bonds.
4. Using the diagram below, label the major parts of enzyme action.
PRODUCTS
SUBSTRATE
ACTIVE SITE
ENZYME
5. Why is the relationship between structure and function important in biological systems?
The structure (shape) of molecules, cells, and organisms as a whole directly determines what
functions they can carry out. For example, Skin cells are flat and thin, which make the ideal for
covering a surface, which is exactly what they do.
The “Big Idea”
B.1.3 Explain how the function and differentiation of
cells is influenced by their external environment,
including temperature, acidity and the concentration of
certain molecules, and that extreme changes in these
conditions may change how a cell functions.
Terms to KNOW & USE
Acidity, temperature, pH, denature, hormones,
enzymes
6. How can extreme changes in temperature or pH affect the structure and function of proteins/enzymes?
Extreme changes in TEMPERATURE or the pH (ACIDITY) of an environment can cause proteins
to change shape. This is called DENATURING. If a protein’s shape changes then its function
will change, meaning that it will no longer be able to the job that it was intended to do.
7. Explain why most organisms require a narrow range of environmental conditions to survive.
Life is supported by a large variety of chemical process that occur all of the time. Chemical
reactions require certain conditions to happen.
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Standard 2: Cellular Structure
Core Standard
Describe features that are common to all cells and contrast those with distinctive features that allow cells to
carry out specific functions.
The “Big Idea”
B.2.1 Describe features common to all cells that are
essential for growth and survival, and explain their
functions.
Terms to KNOW & USE
Nucleus/nucleoid region (prokaryote/eukaryote)
cell/plasma membrane, cytoplasm, ribosome
1. Explain the seven (7) basic characteristics of ALL living organisms and give an example of each.
CHARACTERISTIC
DESCRIPTION
EXAMPLE
Metabolism
Homeostasis
A combination of the chemical reactions an
organisms uses to break down and build up
materials.
A cow eats and digests
grass for energy.
The ability to maintain a relatively constant
internal environment.
Humans’ ability to maintain
a constant internal
temperature.
All organisms are made of one or more cells.
Animals, plants and fungi
are made of multiple cells.
Bacteria and protists are
made up of single cells.
Organisms adapt to changes in their
environment.
Plants growing in the
direction of sunlight.
Organisms get bigger and more specialized
as they get older.
Infants get larger, and are
able to do more complex
tasks as toddlers.
All organisms have DNA, which passes their
genetic make up to their offspring through
either asexual or sexual reproduction.
A dog’s puppies have
similar characteristics as
their mother.
Organisms are able to make more of their
own kind.
Plants producing seeds
that result in more plants.
Cellular Organization
Response to Stimuli
Growth & Development
Heredity/DNA
Ability to Reproduce
2. Complete the following chart with function of common organelles.
ORGANELLE
FUNCTION
The outer, protective layer of a cell. It regulates what enters and leaves the
Cell Membrane
cell.
Nucleus
Cytoplasm
The structure that contains a cell’s DNA. It is the command and control
center.
The space inside of a cell that contains all the organelles. It is filled with a
gel-like substance called cytosol.
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3. List three (3) similarities and three (3) differences between eukaryotic cells and prokaryotic cells. (Give
an example of each.)
Similarities: :
- Both prokaryotes and eukaryotes have a cell membrane
- Both prokaryotes and eukaryotes have DNA (Genetic Material.)
- Both prokaryotes and eukaryotes have cytoplasm.
- Both prokaryotes and eukaryotes have ribosomes.
Differences:
- Eukaryotes have a membrane-bound nucleus, but prokaryotes do not.
- Eukaryotes have a membrane-bound organelles that carry out cell processes, but prokaryotes
do not.
- Eukaryotes undergo mitosis, but prokaryotes undergo binary fission.
EXAMPLES: Prokaryotes: Bacteria. Eukaryotes: Animals, plants, fungi, and protists.
4. List three (3) similarities and three (3) differences between plant cells and animal cells.
Similarities:
- Both plant and animal cells have a cell membrane.
- Both plant and animal cells have mitochondria.
- Both plant and animal cells have a membrane-bound nucleus.
Differences:
- Plant cells have cell wall, but animal cells do not.
- Plant cells contain chloroplasts, but animal cells do not.
- Plant cells contain a central vacuole, but animal cells do not.
The “Big Idea”
Terms to KNOW & USE
B.2.2 Describe the structure of a cell membrane and
Cell membrane, phospholipids, passive
explain how it regulates the transport of materials into
transport, active transport, osmosis, diffusion,
and out of the cell and prevents harmful materials from
concentration gradient, homeostasis
entering the cell.
5. Describe the term "semi-permeable" (or "selectively-permeable) membrane. Why is it important?
A SEMI-PERMIABLE membrane also for the TRANSPORT of certain materials into and out of a
cell, but not others. It is important because cells need certain materials to survive, but if other
materials enter the cell, it could destroy the cell.
6. List two (2) similarities and two (2) differences between passive transport and active transport and give
2 examples of each.
Similarities:
- Both active and passive transport move materials into and out of cells.
- Both active and passive transport can move materials through a semi-permeable membrane.
Differences:
- Active transport requires the cell to use energy, but passive transport does not.
- Active transport can move against the CONCENTRATION GRADIENT, but passive transport cannot.
Examples:
- PASSIVE TRANSPORT: Osmosis, diffusion, facilitated diffusion
- ACTIVE TRANSPORT: Endocytosis, exocytosis, phagocytosis, pinocytosis, ion pumps
7. Describe homeostasis and why it is important to an organism.
Homeostasis is the ability of an organism to maintain a relatively constant internal environment.
This is important be cause cells need certain materials and conditions to survive. They also
have to be able to keep out dangerous materials that could harm the cell.
8. What is a stimulus and explain how an organism’s ability to respond to a stimulus helps it survive?
A stimulus is a change in the environment that causes a response. Organisms must be able to
respond to stimuli so that they can adjust to better survive when conditions change (for
example, plant leaves changing to face sun, bears hibernating, porcupine extending quills in
defense.)
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9. For the following diagrams, draw arrows that show the direction that water diffuses (concentration
gradient) through the membrane. Label the beaker and cell in each diagram as either hypertonic,
hypotonic, or isotonic.
Beaker =
60% Water
Beaker =
90% Water
Beaker =
50% Water
Beaker =
100% Water
Cell =
80%
Water
Cell =
40%
Water
Cell =
50%
Water
Cell =
20%
Water
Beaker A
Beaker B
Beaker C
Beaker D
Beaker: Hypertonic
Beaker: Hypotonic
Beaker: Isotonic
Beaker: Hypotonic
Cell: Hypotonic
Cell: Hypertonic
Cell: Isotonic
Cell: Hypertonic
The “Big Idea”
Terms to KNOW & USE
B.2.3 Explain that most cells contain mitochondria, the
Mitochondria, cellular respiration, chloroplasts,
key sites of cellular respiration, where stored chemical
photosynthesis, ATP
energy is converted into useable energy for the cell and
some cells, including many plant cells, contain
chloroplasts, the key sites of photosynthesis, where the
energy of light is captured for use in chemical work.
10. Complete the following chart with function of common organelles.
ORGANELLE
FUNCTION
The site of cellular respiration, where cells break down glucose into a
Mitochondrion
useable form of energy for the cell (ATP.)
Chloroplast
The site of photosynthesis, where cells convert light energy into usable
energy for the cell (ATP), and stored energy (glucose).
11. Explain the role and importance of ATP in living organisms. Also, explain how energy is released from
ATP.
ATP, or Adenosine Triphosphate is the functional unit of energy for living things. It is made of
an “adenosine” group with three phosphates. When the third phosphate is detached, the
chemical energy that was holding in place is released and can be used by the cell.
The “Big Idea”
Terms to KNOW & USE
B.2.4 Explain that all cells contain ribosomes, the key
Ribosomes, protein synthesis, mRNA, amino
sites for protein synthesis, where genetic material is
acids, rRNA
decoded in order to form unique proteins.
12. Complete the following chart with function of common organelles.
ORGANELLE
FUNCTION
The site of protein synthesis, in which mRNA undergoes transcription to
Ribosome
form chains of amino acids.
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The “Big Idea”
Terms to KNOW & USE
B.2.5 Explain that cells use proteins to form structures, Cilia, flagella, surface area, unicellular,
including cilia, flagella, which allow them to carry out
multicellular
specific functions, including movement, adhesion, and
absorption.
13. Complete the following chart with function of common organelles.
ORGANELLE
FUNCTION
Small, hair-like projections from the outside of a cell which can pulse,
Cilia
causing the cell to move, or create a current to cause food particles to
come close to the cell. They can also be used for absorption.
A long tail-like structure that allows a cell to move through its environment
Flagella
(water).
14. How does the presence of cilia affect the surface area of a cell and how does it that effect how the cell
carries out its important functions?
The presence of cilia increases the surface of a cell. The greater the surface area, the more
space that can be used for absorption. That means that the cell can get more resources from its
surroundings.
Standard 3: Matter Cycles and Energy Transfer
Core Standard
Describe how the sun’s energy is captured and used to construct sugar molecules which can be used as a
form of energy or serve as building blocks of organic molecules.
Core Standard
Diagram how matter and energy cycle through an ecosystem.
The “Big Idea”
Terms to KNOW & USE
B.3.1 Describe how some organisms capture the sun’s Carbohydrate, chemical bond, chemical
energy through the process of photosynthesis by
reaction, producer, autotroph, reactant product,
converting carbon dioxide and water into high-energy
glucose, ATP, carbon dioxide, water, light
compounds and releasing oxygen.
energy, chloroplasts, chlorophyll
1. Write out the chemical equation for photosynthesis.
6CO2 + 6H2O ⇒ C6H12O6 + 6O2
2. Describe the process of photosynthesis using the following terms (underline them as they appear in
your answer: photosynthesis, sunlight, glucose, carbon dioxide, water, oxygen (O2), autotrophs,
chloroplast, pigment, chlorophyll.
Plants are autotrophs, which means they can produce their own food. Plants conduct
photosynthesis by absorbing sunlight in small organelles called chloroplasts which contain a
green pigment called chlorophyll. These chloroplasts take carbon dioxide and water, in the
presence of sunlight, to produce glucose, and oxygen (O2)
The “Big Idea”
B.3.2
Describe how most organisms can combine
and recombine the elements contained in sugar
molecules into a variety of biologically essential
compounds through the process of cellular respiration.
Terms to KNOW & USE
Carbohydrate, chemical bond, chemical
reaction, producer, autotroph, reactant product,
glucose, ATP, carbon dioxide, water, chemical
energy, aerobic respiration, anaerobic
respiration, heterotroph, consumer,
mitochondria
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3. Write out the chemical equation for cellular respiration.
C6H12O6 + 6O2 ⇒ 6CO2 + 6H2O
4. Describe the process of cellular respiration using the following terms (underline them as they appear in
your answer: cellular respiration, glucose, carbon dioxide, water, oxygen (O2), autotrophs,
heterotrophs, mitochondria, ATP, 46, anaerobic, aerobic.
Cellular respiration is the process by which cells take in glucose and oxygen (O2), and produce
energy in the form of 46 ATP molecules, along with carbon dioxide and water. This occurs
mostly in the small organelle called the mitochondria. If oxygen is present, cellular respiration
is aerobic. However, if oxygen is not present, then the process is anaerobic. Cellular
respiration is necessary for all heterotrophs, which are organisms that cannot make their own
food, but is also conducted in autotrophs.
The “Big Idea”
Terms to KNOW & USE
B.3.3 Recognize and describe that metabolism
metabolism
consists of all of the biochemical reactions that occur
inside cells, including the production, modification,
transport, and exchange of materials that are required
for the maintenance of life.
5. Explain why photosynthesis and cellular respiration are often referred to as a cycle.
The products of photosynthesis are essential for cellular respiration to occur. The products of
cellular respiration are essential for photosynthesis to occur. The summary equations for each
process are the exact opposite of the other.
6. What is ATP and why is it important to all living things?
ATP, or adenosine triphosphate, is the functional unit of energy for all living organisms.
Organisms get energy by breaking off the last phosphate group and using the energy stored in
that bond. During cellular respiration, organisms can convert the complex glucose molecule
into many ATP molecules that it can then use to do any number of functions for which the cell
needs energy.
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The “Big Idea”
Terms to KNOW & USE
B.3.4 Describe how matter cycles through an
ecosystem by way of food chains and food webs and
how organisms convert that matter into a variety of
organic molecules.
Food web, food chain, biomass, ecosystem,
carbon cycle, nitrogen cycle, water cycle,
producer/autotroph, consumer/heterotroph,
primary consumer, secondary consumer,
tertiary consumer, carnivore, omnivore,
herbivore, decomposer.
7. Draw a food web in the space to the right using the information provided in the paragraph below. Label
each organisms of one of the following: producer (P), primary consumer (PC), secondary consumer
(SC), or tertiary consumer (TC).
“In the savannahs of Africa there is a complex system of organisms that depend
on each other for survival. The plentiful grass provides food for insects, small
rodents like mice, and gazelles. Trees provide a food source for giraffes. Birds
eat the insects and mice. Hyenas often eat the mice and from time to time a
pack of hyenas will eat a gazelle. Lions, the king of the savannah, will eat
gazelles, hyenas, and giraffes.”
Lions
SC/TC
SC
Insects
PC
Birds
Hyenas
SC
Mice
Giraffes
PC
Gazelles
PC
PC
Grasses
P
Trees
P
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8. Identify and briefly describe the major steps of each of the biochemical cycles below.
CYCLE
MAJOR STEPS/PROCESSES
Photosynthesis (converts CO2 into glucose), Cellular Respiration (converts
CARBON CYCLE
glucose into CO2), Combustion (emits CO2), consumption (exchange of
matter between organisms), Decomposition (all mater returns to soil.)
NITROGEN CYCLE
WATER CYCLE
Nitrogen Fixation (bacteria and lighting convert of atmospheric N2 to
ammonia and nitrates/nitrites that are usable to living things), consumption
(exchange of matter between organisms), Decomposition (all mater returns
to soil.)
Evaporation (converts liquid water to vapor), Transpiration (loss of water
vapor by plants), Condensation (conversion of vapor to liquid water),
Precipitation (liquid or solid water falls to surface), Run-off (precipitation
flows into water sources), Seepage/Percolation (precipitation infiltrates
ground)
The “Big Idea”
Terms to KNOW & USE
B.3.5 Describe how energy from the sun flows through
an ecosystem by way of food chains and food webs and
only a small portion of that energy is used by individual
organisms while the majority of energy is lost as heat.
Energy pyramid, trophic levels,
producer/autotroph, consumer/heterotroph,
primary consumer, secondary consumer,
tertiary consumer, carnivore, omnivore,
herbivore.
9. Label each level of the food pyramid with one or more of the following terms: Tertiary Consumer,
Decomposer, Primary Consumer, Producer, Secondary Consumer, Herbivore, Carnivore, Omnivore.
1. Tertiary Consumer, Carnivore
2. Secondary Consumer, Carnivore (Possible Omnivore)
3. Primary Consumer, Herbivore
4. Producer
5. Decomposer
10. Refer to the diagram in question one. Assume organism “4” started out with 5000kcal of energy.
Calculate how much energy each of the other organisms would receive from the original amount.
4 = 5000kcal
3 = 500kcal
2 = 50kcal
1 = 5kcal
11. Where does most of the energy and matter/biomass in an environment come from and how much is
passed on at each trophic level?
The sun is the primary source of energy of most ecosystems, which is converted by
photosynthetic organisms, where are consumed heterotrophs for their energy. Only about 10%
of the energy from one organism can be passed on to the organism that consumes it as usable
energy. The rest of the energy is lost as heat.
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Standard 4: Interdependence
Core Standard
Describe the relationship between living and nonliving components of ecosystems and describe how that
relationship is in continual flux due to natural changes and human influence.
The “Big Idea”
Terms to KNOW & USE
B.4.1 Explain that the amount of life an environment
Carrying capacity, biotic, abiotic, biodiversity,
can support is limited by the available energy, water,
habitat niche, ecology, limiting factor,
oxygen, and minerals, and by the ability of ecosystems
exponential growth
to recycle the remains of dead organisms.
1. List the hierarchy of biological organization starting with atoms and going up to biosphere.
ATOMS  MOLECULE  MACROMOLECULE  ORGANELLE  CELL  TISSUE  ORGAN
 ORGANISM  POPULATION  COMMUNITY  ECOSYSTEM  BIOME  BIOSHPERE
2. What is the difference between biotic and abiotic factors? List 3 examples of each.
Biotic factors are living parts of an environment, which include, predators, prey, plants,
bacteria, etc.
Abiotic factors are non-living parts of an environment, which include temperature, water, air,
space, etc.
3. Using the graph below, explain what line “A” and line “B” are telling you about the population and how
they are determined?
Line A is the carry capacity, which is the
maximum number or individuals that an
ecosystem can sustain based on the
available resources.
Line B is the actual population, which goes
above the carrying capacity, then, due to
environmental pressures, crashes.
A
B
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The “Big Idea”
Terms to KNOW & USE
B.4.2 Describe how human activities and natural
Biotic, abiotic, invasive/non-native species,
phenomena can change the flow of matter and energy in habitat destruction/alteration, pollution,
an ecosystem and how those changes impact other
sustainability, climate change, natural
species.
disasters, biodiversity
4. Using the following chart, the ways in which humans can impact/disrupt each of the biochemical cycles
listed.
BIOCHEMICAL
HUMAN IMPACTS
CYCLE
If humans use too much water then it can interrupt the supply of water to other
Water Cycle
places and organisms.
Carbon Cycle
Nitrogen Cycle
Burning too many fossil fuels can cause too much carbon to be put into the
atmosphere.
Too much nitrogen can cause soil to be infertile, and can cause other
problems in aquatic ecosystems.
5. How are fossil fuels formed and what environmental effects do they have when they are burned?
Decayed plant and animal material are covered over and after millions of years of
decomposition and pressure, form crude fossil fuels. When they are extracted, refined, and
burned, fossil fuels release energy along with carbon dioxide gas and other participles that can
be harmful to the environment.
6. Refer to question # 5 under “Big Idea” B.4.1. What could happen to the ecosystem if a disease came
through and destroyed all of the mice? What role does biodiversity play?
If the mice all die, then the bird and hyena population would suffer because much of their food
source would be gone. If the hyenas decrease then the lions would have to eat more giraffes
and gazelles, causing their population to decrease. This would also increase competition
among the lions causing their population to suffer. If there were more species that the birds
and hyenas could feed on (more biodiversity) then the impact would be much less.
The “Big Idea”
Terms to KNOW & USE
B.4.3 Describe the potential consequences of
Non-native/invasive species, native/indigenous
introducing a non-native species into an ecosystem and
species, competition, natural resources,
identify the impact it may have on that ecosystem.
habitat, niche, extinction
7. What factors are included in an organism’s niche?
A niche is the role that a species plays in an ecosystem and includes any and environmental
factors that an organism uses or provides. A niche includes what an organism eats, where it
eats, when it eats, and where it lives.
8. Explain the impact that non-native species, such as zebra mussels in the great lakes, can have on an
ecosystem.
Sometimes, non-native species can out compete native species, causing them to starve. Also,
non-native species can become predators of native species without have predators of their own.
This means that they population could grow quickly, while the native species’ populations
would decrease causing a drastic change in the environment.
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The “Big Idea”
Terms to KNOW & USE
B.4.4 Describe how climate, the pattern of matter and
energy flow, the birth and death of new organisms, and
the interaction between those organisms contribute to
the long term stability of an ecosystem.
Biotic/abiotic, biodiversity, population
dynamics, climate, weather, sustainability,
equilibrium, predator/prey, mutualism,
parasitism, commensalism (symbiosis),
competition, migration
9. Complete the following chart by describing the relationships using these terms and their definitions:
parasitism, mutualism, commensalism, competition, and predator-prey.
ORGANISMS
RELATIONSHIP
DEFINITION
Predator/Prey
One species depends on another for its
A lynx hunts and eats a hare.
food source. The species that is hunted
or eaten is called the prey and the
species that does the hunting is called
the predator.
Competition
Two or more organisms/species need the
Zebras and gazelles eat the
same limited resource.
same grass.
Parasitism
One organism/species receives a benefit,
An intestinal worm takes energy
while the other organism is harmed.
from a dog.
A bee pollinates a flower and
Mutualism
Two organisms/species both receive a
gets pollen to make its own
benefit from the relationship.
food.
Cattle stomp the ground while
Commensalism
One organism/species receive a benefit
walking forcing up bugs for the
from the relation while the other neither
egrets to eat.
benefits nor is harmed.
10. Fill in the chart below regarding biomes.
BIOME
CHARACTERISTICS (CLIMATE/ORGANISMS)
Most productive biome. 2 seasons (wet & dry.)
Tropical Rain Forest
Growth occurs year round.
LOCAIONS
Near the equator.
Cold. Largely treeless. Permafrost, or
permanently frozen layer of soil under surface.
Northern most biome.
Tundra
Inland, close to equator.
Desert
Hot. Very few plants (cacti). Very little
precipitation.
Grass is dry which leads to frequent fires that
Tropical to temperate
prevent tree growth. Many species of herding
areas with very little
animals.
humidity.
Pronounced seasons with trees that lose their
Much of the U.S.
Deciduous Forest
leaves in the fall. Moderate temperatures and
(including Indiana).
humidity.
11. Describe the process of succession. (Draw a diagram to help explain your answer.)
Succession is the gradual, sequential re-growth of a community of species in an ecosystem.
Succession begins with simple, or pioneer species that reproduce quickly. The ecosystem
continues to grow into a climax community, which is stable and undergoes very little change.
Grasslands
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Standard 5: Molecular Basis of Heredity
Core Standard
Describe the basic structure of DNA and how this structure enables DNA to function as the hereditary molecule
that directs the production of RNA and proteins.
The “Big Idea”
Terms to KNOW & USE
B.5.1 Describe the relationship between
chromosomes and DNA along with their basic structure
and function.
Nucleotide, chromatin, chromosomes, genes,
adenine, thymine, cytosine, guanine, double
helix, James Watson, Francis Crick, Rosalind
Franklin, nucleus, histones, centromere
1. Explain the shape (form) and function of DNA including the parts that make it up.
DNA is made of nucleotides that form long stands connected by covalent bonds. Two
complimentary strands connect at the nitrogenous bases that are held together by hydrogen
bonds. These nucleotides pair together (Adenine with Thymine, Guanine with Cytosine)
creating a spiraling ladder called a double helix. The different order of the nucleotides codes
for specific traits in organisms.
2. Draw a diagram of a chromosome, including the parts that make them up.
The “Big Idea”
Terms to KNOW & USE
B.5.2 Describe how hereditary information passed
DNA, genes, chromosomes
from parents to offspring is encoded in regions of DNA
molecules called genes.
3. Describe how the inheritance of traits are determined in a diploid organism?
Diploid organisms inherit 2 of each chromosome and therefore have 2 genes for each trait. If
one of those genes codes for a dominant trait, then that will be the trait that appears in the
individual. If both of the genes code for a recessive trait then that will be the trait that appears
in the individual.
The “Big Idea”
Terms to KNOW & USE
B.5.3 Describe the process by which DNA directs the
production of protein within a cell.
DNA, RNA, mRNA, tRNA, rRNA, transcription,
translation, codon, anti-codon, amino acid,
ribosome, nucleus
4. Complete the chart below to show how DNA controls what proteins an organism produces.
DNA CODE
GGG
AAT
CTT
ATA
GCT
mRNA CODE
tRNA CODE
AMINO ACID
CCC
UUA
GAA
UAU
CGA
GGG
AAU
CUU
AUA
GCU
PROLINE (PRO)
LEUCINE (LEU)
GLUTAMIC ACID (GLU)
TYROSINE (TYR)
ARGININE (ARG)
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5. Explain the step-by-step process of transcription (draw a diagram to aid your explanation.)
Transcription is the process
whereby mRNA is made in the
nucleus of a cell. RNA polymerase
unzips and copies the existing DNA
strand using complimentary base
pairs.
6. Explain the step-by-step process of translation/protein synthesis (draw a diagram to aid your
explanation.)
Translation takes place on ribosomes, where are made of rRNA, and is the process whereby
mRNA is decoded by tRNA to make proteins. Codons on mRNA are matched with anti-codons
on tRNA which bring specific amino acids that are used to build a protein chain.
The “Big Idea”
Terms to KNOW & USE
B.5.4 Explain how the unique shape of each protein is
determined by the sequence of its amino acids.
7. Explain how the order and number of amino acids in a protein determines both the structure and
function of the protein. Provide an example.
Proteins are made of chains of amino acids that are determined by the DNA sequence. When
these amino acids are linked together they begin to fold into 3 dimensional shapes. These
shapes are specific to the function of the protein.
Example: An enzyme has a shape that will only fit its active site to one unique kind of
substrate.
15
Standard 6: Cellular Reproduction
Core Standard:
Explain the processes by which new cells are formed from existing cells.
Core Standard:
Explain the cellular processes that occur to generate natural genetic variations between parents and offspring.
The “Big Idea”
Terms to KNOW & USE
B.6.1
Describe and model the process of mitosis and Mitosis, prophase, metaphase, anaphase,
explain the relationship between the genetic make-up of telophase, cytokinesis, diploid, interphase, cell
the parent cell and the daughter cells of both unicellular
cycle, parent cell, daughter cell, asexual
and multicellular organisms.
reproduction
1. Use the chart below to list the steps of mitosis, draw what a cell in mitosis would look like, and
describe what is happening at that phase.
PHASE
DIAGRAM
WHAT IS HAPPENING
(DRAWING)
After the DNA is copied in interphase, the chromosomes in
the nucleus become more dense, pair up with their sister
Prophase
chromatid (copy of itself), attach at a centromere, and the
nuclear membrane starts to dissolve. The centrioles
migrate to opposite poles of the cell.
The nuclear membrane completely dissolves. The
centrioles reach opposite poles and for a mitotic spindle
(structure that the chromosomes attach to.) The
chromosomes line up along the center of the cell.
Metaphase
The chromosomes split at the centromere and the
chromatids migrate to opposite poles.
Anaphase
New nuclear membranes start to form and the
chromosomes start to recoil. The cytoplasm divides in half
and the cell membranes pinch in and the cells separate
during cytokenisis.
Telophase
2. How do the cells formed as a result of mitosis compare to the original cell?
Cells formed by mitosis are genetically identical to the original cell.
The “Big Idea”
Terms to KNOW & USE
B.6.2 Describe how cells of a multicellular organism
Gene expression, environmental conditions
contain the same genetic information, but develop in
different ways due to gene expression and
environmental conditions.
3. Explain how cells differentiate and specialize to perform different functions like skin cells, muscle,
and/or nerve cells.
The genes in cells turn on and off depending on what type of cell it is to become. Skin cell
genes turn on when the cell is going to be skin and turn off when the cell is going to become
muscle. All cells have the same DNA and the same genes. The kind of cell that it becomes
depends on which genes are turned on and off as it is specializing.
16
The “Big Idea”
Terms to KNOW & USE
B.6.3 Describe and model the process of meiosis and
explain the relationship between the genetic make-up of
the parent cell and the daughter cells (gametes).
Gametes, germ cell, meiosis, prophase I,
metaphase I, anaphase I, telophase I, prophase
II, metaphase II, anaphase II, telophase II,
diploid, haploid, centromere, homologous
chromosomes, chromatid.
4. Use the chart below to list the steps of meiosis, draw what a cell in meiosis would look like, and
describe what is happening at that phase.
PHASE
DIAGRAM (DRAWING)
WHAT IS HAPPENING
In prophase I, the nuclear membrane dissolves and the
chromatin condenses into tightly packed rods, or
Prophase I
chromosomes. (Similar to mitosis.)
Metaphase I
Anaphase I
Telophase I
Prophase II
Metaphase II
Anaphase II
Telophase II
In metaphase I, the chromosomes line up at the equator of
the cell, but unlike mitosis, the chromosomes line up in
pairs. Centrioles move to the poles. The mitotic spindle
forms, which is a series of microtubules and filaments that
give the cell structure during division. During metaphase,
segments of DNA can “cross-over”, leading to genetic
variation.
In anaphase I, the homologous pairs of chromosomes
separate and move toward the poles of the cell and the
cell elongates.
In telophase I, the chromosomes reach the opposite
poles and the cell begins to cut itself into two halves at
the cleavage furrow. The nuclear membranes begin to
form around the chromosomes. Telophase I is
followed by cytokinesis in which the two halves of the
cell separate into two.
In prophase II, the nuclear membranes of the two cells
dissolve and the chromatin condenses into tightly
packed rods, or chromosomes, however, the DNA has
not been in interphase, and could not be copied.
In metaphase II, the chromosomes line up at the
equator of the cells and centrioles move to the poles.
The mitotic spindle forms, which is a series of
microtubules and filaments that give the cells structure
during division. (Similar to mitosis.)
In anaphase II, the chromosomes split at the
centromere into sister chromatids. The chromatids
move toward the poles of the cells and the cells
elongate. (Similar to mitosis.)
In telophase II, the chromatids reach the opposite poles and
the cells begin to cut themselves into two halves at the
cleavage furrow. The nuclear membranes begin to form
around the chromatids. Telophase II is followed by
cytokinesis in which the two halves of the cells separate into
four cells, each with half the chromosomes as the original
germ cell.
17
5. What is the difference between diploid and haploid?
Diploid cells have 2 copies of each chromosome, and have a chromosome number of 2n.
Haploid cells have only one copy of the chromosomes and have a chromosome number of n.
Body, or somatic cells, is diploid. Gametes, or sex cells, are haploid because when they fuse
the zygote will be diploid.
6. How do the cells formed as a result of meiosis compare to the original cell?
Cells formed through the process of meiosis are different than the original cell They contain
only half the number of chromosomes of the original. Each of the resulting 4 cells has a
different combination of the genetic material.
The “Big Idea”
Terms to KNOW & USE
B.6.4 Explain how, in sexual reproduction, crossing
Sexual reproduction, crossing over,
over, independent assortment, and random fertilization,
independent assortment, random fertilization,
result in offspring that are genetically unique from the
haploid, diploid
parent cells.
7. List three (3) similarities and three (3) differences between cells produced by mitosis and cells
produced by meiosis. (Give an example of each.)
Similarities:
Chromosomes condense, line up in the middle and separate.
Differences:
Crossing over happens in meiosis, there are 2 divisions in meiosis, Meiosis results in 4
genetically different cells—mitosis results in 2 genetically identical cells
8. Explain how the following processes lead to genetic variations in offspring produced by sexual
reproduction.
PROCESS
DESCRIPTION/HOW IT CAUSES GENETIC VARATION
Homologous sections of the sister chromatids trade sides creating DNA
Crossing Over
strands that are different from the original
Independent Assortment
Random Fertilization
The chromosomes are separated from one another independently from the
other chromosomes.
The sperm that might fertilize an egg are all different from each other. The
specific sperm that gets to the egg first will determine it’s traits and each
sperm is different.
9. Explain how the chromosomes of 2 parents combine to form the unique combination of chromosomes
in a offspring through sexual reproduction.
Diploid Parents each make haploid gametes which contains half the number of chromosomes
as the parent. These gametes combine to form a diploid offspring that has a unique set of
chromosomes due to the genetic differences listed above.
18
Standard 7: Genetics
Core Standard:
Explain how the combination of genetic information from parents determines the unique characteristics of their
offspring.
The “Big Idea”
Terms to KNOW & USE
B.7.1 Distinguish between dominant and recessive
Gregor Mendel, genes, alleles, dominant,
alleles and determine the phenotype that would result
recessive, homozygous dominant, homozygous
from the different possible combinations of alleles in an
recessive, heterozygous, genotype, phenotype
offspring.
1. Explain why Gregor Mendel is considered the “Father of Genetics”, and what contributions he made to
the field.
In 1843, a monk named Gregor Mendel was in charge of the garden at his monastery. He began
to make observations about the different traits of pea plants (seed color, shape, height, etc…)
Then he wondered what would happen if pollen from a pea plant with one trait would crosspollinate a plant with a different trait. Mendel started with true-breeding, or purebred plants that,
when self-pollinated, always produce offspring with the same trait. He then cross-pollinated
plants with opposite purebred traits (purple flowers with white flowers.) The result was that the
first filial generation (F1) all produced purple flowers. This indicated that the genetic code for
purple was dominant because it overpowered the genetic code for white. Mendel then crosspollinated the plants from the F1 generation to for the F2 generation and something changed. He
got 75% purple flowers and 25% white flowers. The same thing happened with other traits, like
pod color. This indicated that the recessive trait could resurface. It also indicated that all
plants must have a pair of genes for each trait.
2. Explain the Law of Independent Assortment and why it is important.
Alleles of different genes are separate from one another during gamete formation. Because of
this each gamete gets one of each chromosome.
3. Explain the Law of Segregation and why it is important.
The copies of a gene separate so that each gamete receives only one copy. This means that
each fertilized egg gets a haploid set of chromosomes from each parent resulting in a diploid
set.
4. Explain what is meant by each genotype (allele combination), list how you would represent the
genotype in a Punnett square (letters), and describe the phenotype that results from it.
GENOTYPE
Homozygous Dominant
DESCRIPTION (ALLELES)
Homozygous refers to an
organism that has two alleles
that are both dominant.
Homozygous Recessive
Homozygous refers to an
organism that has two alleles
that are both recessive.
Heterozygous
Heterozygous refers to an
organism that has two
different alleles (one dominant
and one recessive.)
LETTERS (Use G)
PHENOTYPE
GG
Dominant
gg
Recessive
Gg
Dominant
19
The “Big Idea”
Terms to KNOW & USE
B.7.2 Describe dominant, recessive, codominant, sex- Dominant, recessive, codominance, sex-linked,
linked, incompletely dominant, multiple allelic, and
incomplete dominance, multiple allele,
polygenic traits and illustrate their inheritance patterns
polygenic, genotype, phenotype, Punnett
over multiple generations.
square, pedigree, carrier
5. Explain what is meant by each inheritance pattern, describe the phenotype that results from it and
provide a specific example.
INHERITANCE
DESCRIPTION
POSSIBLE
ACTUAL EXAMPLE
PATTERN
PHENOTYPES
A flower with white
Codominance is expressed when
2 Dominants
there is more than one dominant
(RR = Red, BB= and red are both
dominant and the
Codominace
trait and both are expressed
Blue)
flowers bloom as
(physically.)
1 Combination
white with red spots.
(RB = Red &
Blue)
If black is the
Incomplete dominance is expressed
2 Dominants
when a dominant trait does not
(RR = Red, BB= dominant fur color for
a dog and white is
Incomplete Dominance completely dominate and a blend of
Blue)
also dominant, the
both the dominant and recessive trait 1 Combination
dog would appear
are expressed (neither complete)
(RB = Purple)
grey.
Multiple Allelic Traits
Generally there are two alleles, the
dominant and the recessive. Some
traits have more than two alleles
which results in more than 2
possible phenotypes.
Polygenic Traits
Some traits are influenced by genes
on located on multiple
chromosomes. The frequency of
the genes determines how the
phenotype is expressed.
2 Dominants
and 1
recessive
(IAIA or IAi = A
IBIB or IBi = B
ii = O)
Light, medium,
dark.
Blood types
Hair, skin, and eye
color.
6. Explain why the inheritance pattern of sex-linked traits differs from autosomal traits and provide 2 examples.
Sex-linked traits are located on the X chromosome. They are inherited in different patterns than
autosomal traits in men because men only inherit one X chromosome, where women inherit 2. If the X
chromosome he inherits has a recessive allele then he will have the recessive trait. This means men
inherit sex linked-traits more often than women. EXAMPLES include: Male pattern baldness, color
blindness, hemophilia.
The “Big Idea”
Terms to KNOW & USE
B.7.3 Determine the likelihood of the appearance of a
Gametes, Punnett square, monohybrid cross,
specific trait in an offspring given the genetic make-up of homozygous dominant, heterozygous,
the parents.
homozygous recessive, probability
7. Compete the following Punnett squares and calculate the probabilities of each genotype and
phenotype.
H
(a)
Mom is homozygous dominant for her widow’s peak (hairline),
but dad does not have a widow’s peak (Use the letter H.)
Genotypes:
Probability:
Hh
4 out of 4 (100%)
Phenotypes:
Probability:
Widows Peak
4 out of 4 (100%)
H
h
Hh
Hh
h
Hh
Hh
20
(b)
(c)
Mom is heterozygous for her ability to curl her tongue (T), but dad cannot
curl his tongue.
Genotypes:
Probability:
Bb
bb
2 out of 4 (50%)
2 out of 4 (50%)
Phenotypes:
Probability:
Can Curl Tongue
Cannot Curl Tongue
2 out of 4 (50%)
2 out of 4 (50%)
1 out of 4 (25%)
2 out of 4 (50%)
1 out of 4 (25%)
Phenotypes:
Probability:
Dimpled
Not Dimpled
3 out of 4 (75%)
1 out of 4 (25%)
b
b
Bb
bb
b
Bb
bb
Mom is heterozygous for dimples (D), and so is dad.
Genotypes:
Probability:
DD
Dd
dd
B
D
D
d
d
BB
Bb
Bb
bb
8. Using the pedigree below, label each individual with the correct genotype, determine what type of
inheritance pattern is shown and explain how you came to that conclusion.
This is a recessive inheritance pattern. You can
Aa
Aa
determine this because in both Generations I (1 & 2)
and II (5 & 6), neither parent has the trait, but are
able to pass it on to their offspring. If the trait were
dominant, the parents would have to express it.
Aa
Aa
aa
Aa
aa
aa
The “Big Idea”
AA or Aa AA or Aa
Terms to KNOW & USE
B.7.4 Explain the process by which a cell copies its
X-rays, radioactivity, environmental chemicals,
DNA and identify factors that can damage DNA and
oxygen radicals, semi-conservative DNA
cause changes in its nucleotide sequence.
replication, DNA polymerase
9. Explain the step-by-step process that a cell uses to copy its DNA (DNA Replication).
Cells make a copy of their DNA by first separating the 2 strands and then using DNA
polymerase to pair nucleotides to the existing strands of DNA creating 2 new DNA molecules.
This is called semi-conservative because the original strands of DNA are used as the template.
After the DNA polymerase brings in new nucleotides the cell double checks then new DNA
strands to make sure they are correct and then DNA double helix returns to its shape.
10. Identify factors that can damage DNA and how they can cause changes in its nucleotide sequence.
Radiation, chemicals called carcinogens & mutagens, and errors in cellular processes
(including DNA Replication and Transcription) can result in random changes in the DNA
sequence, which are called mutations.
21
The “Big Idea”
Terms to KNOW & USE
B.7.5 Explain and demonstrate how inserting,
Mutation, insertion, substitution, deletion, point,
substituting or deleting segments of a DNA molecule can frameshift, cancer
alter a gene, which is then passed to every cell that
develops from it and that the results may be beneficial,
harmful or have little or no effect on the organism.
11. Compare the DNA strands in the diagram below, determine what type of mutation has occurred, explain
what that means and classify it as either a point or frameshift mutation.
DNA STRANDS
TYPE OF
DESCRIPTION
POINT OR
(ORIGNIAL/MUTATION)
MUTATION
FRAMESHIFT
An extra nucleotide is
A-C-G-T-A-G-G-C-T-A-G-T-G-A-A
Insertion
inserted causing every
Frameshift
other nucleotide to be
shifted forward one spot.
A-C-G-T-A-G-G-G-C-T-A-G-T-G-A
(9th Nucleotide: Inserted
“”C”)
A-C-G-T-A-G-G-C-T-A-G-T-G-A-A
Deletion
A-C-G-T-A-G-G-C-A-G-T-G-A-A-T
A-C-G-T-A-G-G-C-T-A-G-T-G-A-A
A-C-G-T-A-G-G-C-T-A-T-T-G-A-A
Substitution
A nucleotide is removed
causing every other
nucleotide to be shifted
back one spot.
(9th Nucleotide: Removed
“T”)
One nucleotide is switched
out with another resulting a
error in that spot only.
(11th Nucleotide: “T”
substitutes “G”)
Frameshift
Point
12. Explain how and why some mutations can be passed from parents to their offspring, but others cannot.
Offspring receive their genetic material from their parents gametes (sperm and egg.) If a
mutation occurs in the DNA located in the sperm and/or egg, then the mutation will be present
in the offspring. If a mutation happened in the somatic (body) cells then the mutation will not be
passed on to the next generation.
13. What is cancer and how does it occur?
Cancer is a uncontrolled growth and division of cells. It results from a mutation, which is a
change in the order of nucleotides of DNA/RNA.
14. A great deal of research on the causes of and a possible cure for cancer focuses on mitosis. Why?
Mitosis is the process by which cells divide. Cancer is the uncontrolled division of cells. By
studying the process of mitosis, we can better understand what makes cells divide and how to
stop it from happening in cancerous cells.
22
Standard 8: Evolution
Core Standard
Describe how biochemical, fossil, anatomical, developmental, and genetic findings are used to determine
relationships among organisms, producing modern classification systems.
Core Standards
Describe how modern evolutionary theory provides an explanation of the history of life on earth and the
similarities between organisms that exist today.
The “Big Idea”
Terms to KNOW & USE
B.8.1 Explain how anatomical and molecular
Homologous structures, analogous structures,
similarities among organisms suggests that life on earth
vestigial structures, cladogram, fossil
began as simple, one-celled organisms about 4 billion
years ago and increasingly complex, multicellular
organisms evolved later.
1. Give a description of each type of structure in the chart below and give an example of each.
STRUCTURE TYPE
DESCRIPTION
EXAMPLE
Structures that have both a similar form
The arm of a human and the
Homologous
and function.
flipper of a dolphin.
Analogous
Vestigial
Structures that share a similar function but
have a different form.
Wings of a bat and wings of a
moth.
Structures that share a similar form, but
have no real function.
Hip bone of a whale.
2. Use the diagram to the right to explain how the 3 species are related.
Even though the 3 structures do different things, the anatomical
evidence shows that they have a similar bone structure. This
would indicate that even though these species are not the same,
they have common traits that were passed down to them from
their ancestors.
3. Refer to the cladogram to the right. What
traits do amphibians and rodents share?
Vertebrae, Bony Skeletons, Four
Limbs, and Amniotic Eggs.
4. Refer to the cladogram to the right. Which
more closely related to crocodiles, rodents
birds. Explain how you came to your
conclusion.
Birds and crocodiles are more closely
related because they have more traits
common and share a more recent
common ancestor.
is
or
in
23
The “Big Idea”
Terms to KNOW & USE
B.8.2 Explain how organisms are classified and
named based on their evolutionary relationships into
specific taxonomic categories.
5. Fill-in the chart below with the characteristics that identify organisms in that kingdom.
KINGDOM
TYPE OF CELL
NUMBER OF CELLS
ENERGY SOURCE
(Unicellular and/or Multicellular)
(Prokaryotic or Eukaryotic)
(Autotroph or Heterotroph)
Eukaryote
Multicellular
Autotroph
Plant
Animal
Eukaryote
Multicellular
Heterotroph
Fungi
Eukaryote
Uni or Multicellular
Heterotroph
Protista
Eukaryote
Unicellular
Auto or Heterotroph
Archebacteria
Prokaryote
Unicellular
Autotroph/Hetrotroph
Eubacteria
Prokaryote
Unicullular
Autotroph/Hetrotroph
6. List the eight modern levels of taxonomic organization in order from the group with the largest
numbers of organisms to the group which is most specific and has only one kind of organism in it.
Domain
Most General
Kingdom
Phylum
Class
Order
Family
Genus
Species
The “Big Idea”
Most Specific
Terms to KNOW & USE
B.8.3 Use anatomical and molecular evidence to
establish evolutionary relationships between organisms.
7. Using the amino acid sequences, determine which 2 organisms are most closely related and explain
how you came to that conclusion.
Human Amino Acid Sequence:
The human and bat are more closely related.
MET-PRO-VAL-THR-TYR-PHE-GLU-ASP-ASP
This is supported by the fact that their amino
acid sequence (which is determined by their
Penguin Amino Acid Sequence:
DNA) only have one amino acid different. The
MET-PRO-VAL-ASP-ASP-THR-TYR-PHE-GLU
more similar the DNA the more closely related
organisms are.
Bat Amino Acid Sequence:
MET-PRO-VAL-THR-TYR-PHE-LEU-ASP-ASP
Alligator Amino Acid Sequence:
MET-PRO-VAL-ISO-ARG-PHE-LEU-GLU-ASP
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The “Big Idea”
B.8.4 Describe how species change over time as a
result of the environmental, genetic and reproductive
forces for which they are best-suited.
Terms to KNOW & USE
Evolution is the consequence of the interactions of:
(1) the potential for a species to increase its
numbers,
(2) the genetic variability of offspring due to
mutation and recombination of genes,
(3) a finite supply of the resources required for life,
and
(4) the ensuing selection from environmental
pressure of those organisms better able to survive
and leave offspring.
8. Give a description of each driving force behind natural selection in the chart below and give an example
of each.
DRIVING FORCE
DESCRIPTION
EXAMPLE
Production of
A species has more offspring than can
Roaches have hundreds of offspring
larger numbers of survive to reproductive maturity.
and are well suited, but pandas have
offspring
few offspring.
Ability to
Individuals compete against each other
A jaguar can fun fast and out compete
compete
for limited resources.
other predators for food.
Genetic Variation
Non-Random
Mating
The individuals in a population have
different traits ranging from color & size
to strength& speed.
The organisms that survive due to their
fitness for the environment reproduce
and pass the favorable traits to their
offspring.
Rabbits that have a variety of colors of
fur are more likely to survive if the
environment changes (Snowshoe hare.)
Peacocks often mate with the male with
the largest plumage.
9. How would the gene pool of a species be affected to the following responses to environmental
changes?
RESPONSE
EFFECT ON GENE POOL
Go to a place where the environmental conditions are more favorable.
Migration
Adaptation
Death
Change patterns of behavior to respond to the new environment.
If an organism is unable to adapt to its environment or move to an
environment in which it can survive then it will die. (IMPORTANT: Dead
organisms do not reproduce.)
10. Explain the difference between convergent and divergent evolution.
Convergent evolution is the process by which unrelated organisms become more and more
alike due to similarities in their environmental pressures.
Divergent evolution is the process by which related organisms become more and more different
due to differences in their environmental pressures.
11. Explain why a population of rabbits that have been isolated by mountains may evolve in a different way
than the same species that has been allowed to migrate over a large area.
Isolation of a species limits their gene pool. Without new genetic variations, the mountain
rabbits aren’t likely to change much over time. Migration of the other rabbits results in different
environmental pressures, cause increased variation.
25
The “Big Idea”
Terms to KNOW & USE
B.8.5 Describe how organisms with beneficial traits are
Survival of the fittest, natural selection,
more likely to survive, reproduce, and pass on their
environmental pressures,
genetic information due to genetic variations,
environmental forces and reproductive pressures.
12. Explain why Charles Darwin is considered the “Father of Evolution”, and what contributions he made to
the field.
In the 1830’s, a British scientist named Charles Darwin was traveling on the HMS Beagle in the
Galapagos Islands. He was amazed and the diverse and unique organisms that he observed.
He also noted that despite their diversity, almost all of the organisms had certain
commonalities. Darwin continued to make observations and was convinced that these
organisms must have some ancestral link in their past. In other words, species have the ability
to change over time, and those changes can become so varied that new species can be formed
as a result of these changes. This is called the theory of evolution.
13. Explain what Charles Darwin meant by the term “natural selection”.
Natural selection is the process by which organisms with favorable traits survive to reproduce.
He used the term “survival of the fittest, and suggested that the four driving forces to natural
selection were overproduction (more offspring survive to sexual maturity), genetic variation
(more options available to respond to change), struggle to survive (competition), and differential
reproduction (preferred traits attract more mates.)
14. Explain why white rabbits (snowshoe hare) are commonly found in the northern parts of North America,
but are not found in southern regions.
The mountain rabbits are likely to evolve to be lighter in color if there is a lot of snow because
they will be able to better blend in and avoid predators. They would also likely evolve to live
under bushes and brush because it is difficult to burrow into the rocky coil of the mountains.
Because there is more area in the other population, there is likely to be a great diversity in the
organisms because there is a greater diversity of environmental pressures.
The “Big Idea”
Terms to KNOW & USE
B.8.6 Explain how genetic variation within a population
(i.e., a species) can be attributed to mutations as well as
random assortments of existing genes.
(See Standard 7)
The “Big Idea”
Terms to KNOW & USE
B.8.7 Describe the modern scientific theory of the
fossil record, anatomical similarities,
origins and history of life on earth and evaluate the
homologous structures, DNA, nucleotide
evidence that supports it.
sequence
15. Describe the modern scientific theory of the origins of life on earth and describe 3 types of evidence
that is used to support it.
Modern scientific theory suggests that life begin in the harsh oceans of early earth as singlecelled prokaryotes that, over time, evolved and became more complex. Ultimately, that means
that all organisms can be traced back to a common ancestor. Scientists use the fossil record to
show relationships between species of different eras. They use biochemical analysis to show
similarities and differences in the DNA of related organisms. They also use anatomical and
embryological evidence to show that seemingly unrelated organisms develop and function in
very similar ways.
26