Transcript Biology EOC review

Biology EOC review
answers
Ch 1: scientific method
1.
2.
3.
4.
5.
A
D
D
B
C
6. C
7. D
8. C
9. A
10. D
11.
12.
13.
14.
15.
C
C
B
C
C
16.
17.
18.
19.
20.
D
B
D
D
B
21. A . State the problem (in question form)
B. Collect information about the problem
C. Form a hypothesis (a possible answer) ( must be
testable)
D. Design and conduct an experiment (use an
experimental group with a variable, and a control group
without the variable.)
E. Record observations and data
F. Check results; redo experiment as needed
G. Draw your conclusions (accept or reject hypothesis)
H. Communicate your results.
22. Hypothesis is a possible answer, or an educated guess.
Theory is a general statement supported by many
scientific observations and experiments, and
represents the most logical explanation of the evidence.
23. A research plan is necessary before testing a
hypothesis to ensure that there is only one
variable, and that there are valid controls.
24. A clear statement of a hypothesis is important
because it could lead to the answer of a
question.
25. A scientist can collect and organize data in
tables, charts, and graphs
26. The results of one experiment cannot become
a theory; a theory must be supported by
MANY experiments and observations.
27. B
28.
control group: solution with no salt
experimental group 1 5% salt
experimental group 2 10% salt
experimental group 3 15% salt
two conditions constant: water temperature,
number of shrimp, amount of solution in
containers
29. C (D)
30. C
31. -hypothesis: if we grow the plants in acidic
soil, they will be a different color.
-The control group will be grown in (normal)
slightly basic soil.
-Both the experimental and control groups
should be in the same amount of soil,
should receive the same amounts of
water and sunlight.
-one piece of evidence supporting my
hypothesis would be flowers that were
a color (not white)
32. Corn seedlings are only one type of plant, so to
make generalizations about plants, many types
should be studied.
33. It is important to include all steps of an experiment so
that other researchers can repeat it and verify the
results
34. A hypothesis should be changed whenever new,
conflicting information is found
35. Charles Darwin kept a journal so that he could keep
track of all details and data, as well as new ideas.
36. -Question: can seeds travel long distances in the ocean
and still able to grow?
-Hypothesis: If I soak seeds in salt water, and then
plant them, they will grow.
-Experiment: he soaked many different kinds of seeds,
for short and long periods of time, and then planted
them.
Chapter 2: Laboratory tools and
techniques
1. C
2.
3.
4.
5.
B
B
D
B
6.D
7.C
8.D
9.C
10.D
11.D
12.D
13.D
16.A (and B)
14.A
17.A
15.C (A) 18.A
19.D
20.B
21. C
22. C
23. A
24. D
25. A 10-ml graduated cylinder, should be read at
eye-level, to the bottom of the meniscus
26. Measurements are useful for accuracy so
reliable, valid, information can be obtained
and analyzed to draw conclusions.
27. Scientists use tools and instruments to
improve the accuracy of their observations.
28. A. Use a medicine dropper to place a drop of
water on the slide.
B. Use the medicine dropper to place the
specimen into the water on the slide.
C. Gently lower a coverslip, one edge down at
a 45-degree angle first
D. Add a drop of stain at one edge , and draw
it through with a piece of paper towel.
29. Similarities: both are used to magnify
images more than 250,000 times, and they
use electron beams and magnetic lenses.
Differences: the TEM passes beams
through a specimen. The SEM passes
beams over the surface.
30.
volume: liters
temperature: degrees Celsius
mass: kilograms
length: meters
31. (safety rules)
32. They could rub a piece of each food on a piece
of brown paper bag and look for grease.
33. Scientists have used electron microscopes to
see much smaller objects.
34. Both types of microscopes are used to magnify
small objects. Light microscopes can be used
to see living objects; electron microscopes can
be used to see much smaller objects, because
no light is involved.
35. Don’t bother.
Ch 3: Organic Molecules: from
Atoms to Cells
1.
2.
3.
4.
5.
6.
7.
B
D
B
A
D
B
C
8. D
9. B
10. A
11. A
12. C
13. A
14. A
15. B
16. B
17. B
18. A
19. B
20. D
21. B
22. To maintain high levels of organization
necessary to stay alive, organisms require
energy.
23. Carbon is of special importance to living things
because organic compounds are built on a
“skeleton” or framework of carbon atoms.
24. Four important functions of organic
compounds are: capturing and transforming
energy, building new structures, storing
materials, and repairing structures.
25. Athletes need lots of complex carbohydrates
during training to supply energy.
26. C
27. B
28. They have different amino acid sequences, and
different conformations.
29. C
30. Three important characteristics of proteins:
a. Made of subunits called amino acids
b. Main functions are to build new materials, transport
substances, send signals, provide defense, control
chemical and metabolic activities
c. Structure and function is determined by the
sequence of the amino acids, and the conformation
(shape) of the molecule.
31. The particular proteins in our body depend
upon our DNA, because the nucleotide
sequence determines those proteins.
32. Tissues are groups of cells, such as nervous
tissue that is made up of nerve cells or
neurons. Organs are made of tissues working
together, such as the brain which is made of
nervous, blood, and connective tissues.
33. Main levels of organization:
atoms, molecules, organic compounds,
organelles, cells, tissues, organs, organ
systems, organisms.
34. Evolution explains the problems with weight loss in
that a favorable adaptation would be the ability for a
person’s metabolism to slow down when facing
starvation. Also, a person whose fat cells have been
emptied will feel hunger and try to “fill them up” again.
35. Exercise is a healthier way to lose weight because it
increases the amount of energy used by the body. It
also increases the amount of muscle tissue, which
burns more calories than other types of body tissues
even when resting.
36. Anorexia and bulemia both are both eating disorders
that result in severe weight loss, which may be fatal.
Anorexia is a refusal to eat, whereas bulemics eat and
then eliminate the food. Anorexics appear unhealthy,
while bulemics may appear healthy.
Chapter 4: Homeostasis and
Enzymes
1.
2.
3.
4.
5.
6.
7.
8.
B
B
A
A
A
B
D
A
9. A
10. A
11. B
12. D
13. A
14. C
15. A
16. B
17. A
18. C
19. B
20. C
21. B
22. A
23. C
24. ribosomes: where proteins are built
lysosomes: break down food
mitochondria: release energy from food
nucleus: information storage, control center
golgi apparatus: packages many materials
vacuoles: store materials such as food or
waste
chloroplasts: convert sun’s energy into food
25. The cell membrane is selectively permeable
because it allows some substances to pass
through but not others.
This is important because cells need certain
molecules inside but some should be kept outside.
26. Arrow A shows molecules going from an area
of less concentration to an area of greater
concentration, which is active transport because
energy is needed to go against the
concentration gradient. Passive transport is
different in that it doesn’t need energy.
27. Receptor molecules, proteins on the surface
of a cell membrane, allow certain molecules to
attach (chemical messengers) thereby enabling
communication between cells.
28. Stability in an organism is maintained by
integration or making all body parts work
together, and control or acting in an organized
and appropriate manner. In animals, this job is
done by the nervous system and the endocrine
system.
29. Cells communicate with each other by having
certain chemicals move in or out of them.
Receptor proteins in the cell membrane act as
docking sites for these chemicals.
30. Every nerve cell does 3 things; it receives,
conducts, and sends nerve impulses.
31. A nerve impulse is the movement of electrical
voltage (energy) changes along the length of a
neuron. The cell membrane is the most
important part of this because electrical voltage
is created by the rapid movement of positive ions
across a cell membrane. These changes trigger
changes further along the membrane.
32. When a nerve impulse reaches the end of a
neuron, it causes the release of chemicals, which
diffuse across the space to the next cell (the
synapse) to the next nerve cell, which causes the
impulse to be carried along.
33.
34. The energy stored in chemical bonds can
be transferred to other newly formed
chemical bonds or released as heat or
light. Cells use this energy for active
transport, heat, or other cell functions.
35. If a cell’s mitochondria were removed, it
would not be able to release energy from
food molecules
36. The spleen was removed to cure leukemia
37. The pancreatic tissues were used for
research; they produced a certain protein
which was later used to make a new
medicine.
38. The legal system was used to determine
whose rights should have precedence,
those of the cell-donor or the researchers.
Chapter 5: Homeostasis and
Enzymes
1.
2.
3.
4.
5.
6.
7.
8.
C
C
A
B
D
C
C
B
9.
10.
11.
12.
13.
14.
15.
16.
17.
D
C
B
C
B
B
B
B
D
18.
19.
20.
21.
22.
23.
24.
25.
26.
A
D
C
B
D
C
B
B
A
27.
28.
29.
30.
31.
32.
33.
34.
A
C
C
D
C
C
B
A
35. Being multicellular increases and organism’s
ability to maintain homeostasis and survive
because it has many different structures and
systems to protect it from external changes.
36. A body cell will be more likely to survive than an
amoeba because the body cell is multicellular.
37. Intercellular fluid is important for homeostasis
because many substances are dissolved in it,
and it allows substances to be exchanged
between cells and blood in the capillaries.
38. B
39. A feedback mechanism has 3 parts:
•
a sensor – something that can detect a change
•
a control unit – something that can recognize the
correct level of something
•
an effector-something that can make changes
40.
•
•
•
•
•
Blood sugar level is too high
pancreas releases insulin (hormone) into blood stream
insulin reduces levels of glucose
blood sugar levels are too low
pancreas releases glucagon to raise blood sugar levels
41. When we exercise, there is an increase in the CO2 levels
in the blood and intercellular fluid, released by muscle
cells breaking down organic compounds for energy. A
structure in the brain detects these increased levels in the
blood passing through the brain, and in the fluid around
the brain cells. The brain sends signals to the chest to
increase the rate of breathing and the amount of air taken
in with each breath. These changes increase the levels
of gas exchange in the lungs, lowering the levels of CO2
in the blood. These lower levels are then detected in the
brain, reversing the other responses.
42. D
*43. Rising external temperatures will be detected by sensors
in the skin, which will send a message to the brain, which
will increase blood vessel dilation and sweating.
Homeostasis means that the body must maintain
constant internal temperatures, regardless of what is
happening outside the body.
44. Staying in the shade prevents the body from
heating up too much in the sun.
45. Stomata, or openings, surrounded by guard
cells on the surface of a leaf, control the loss of
water. When water is abundant, the guard
cells fill (by osmosis) and open to allow water
to evaporate. When water is scarce, they lose
water, and close, preventing water loss.
46. Contractile vacuoles and guard cells both help
maintain levels of water within organisms.
47. Four organ systems used in homeostasis:
• Excretory system: removes wastes and
regulates the chemistry of the body’s fluids
• Nervous system: uses electrochemical
impulses to regulate body functions
• Endocrine system: produces hormones
(chemical messengers) that help regulate
bodily functions
• Immune system: defends the body from
dangerous substances and harmful
microorganisms.
48. D
49. If the temperature of the solution was
increased, the rate of the reaction would slow
down, because enzymes need a certain
temperature to function.
50. A person with a high body temperature would
possibly die because enzymes change their
shape if the temperature changes, and
therefore their function.
51. We must maintain a neutral pH because any
changes affect an enzyme’s shape and its
function.
52. Life on the ISS is different from Earth in that
there is no downward pull from gravity. There is
no up or down, no floors or ceilings. Crews live
in a relatively small space, and sleep wherever
they feel comfortable .
53. The effects of weightlessness are interesting to
scientists because we are not aware of our
bodies’ responses to gravity until we leave the
Earth.
54. Some of the adaptations of the body to living in
a world with gravity include use of signals from
our eyes, from the fluid-filled tubes in our ears,
from pressure receptors on the bottoms of our
feet, and from the distribution of liquids in blood
vessels.
Ch 6: Photosynthesis and
respiration
1.
2.
3.
4.
5.
6.
7.
B
B
C
D
B
C
D
8. D
9. C
10. C
11. A
12. B
13. B
14. C
15. B
16. A
17. B
18. C
19. C
20. D
21. Autotrophs make their own food.
Heterotrophs ingest food that they don’t make.
22. Photosynthesis is a bridge between the living
and non-living worlds because inorganic
compounds are converted into organic
compounds, and recycled again and again.
23. The structure of leaves enables
photosynthesis by having chloroplasts which
use sunlight, and are located to get maximum
exposure. They also have stomata with guard
cells, which allow exchange of the gases
carbon dioxide and oxygen, and which also
control loss of water to the atmosphere.
24. This equation show photosynthesis. The
products are glucose and oxygen.
25. Cellular respiration is the opposite of
photosynthesis because the products of one
are the reactants for the other.
26. Photosynthesis is being controlled in this set
up.
27. An astronaut would cause changes in the
space station atmosphere by adding CO2 and
taking out O2.
28. Turning on more lights would increase
photosynthesis, so there would be more O2
and less CO2 in the air.
29. Euglena carries out both photosynthesis
and cellular respiration.
photosynthesis:
6CO2 + 6 H2O -> C6H12O6 + 6 O2
30. This process is essential for the survival
of euglena because euglena need to
make their own food.
31. Photosynthesis provides food and oxygen for all
living things.
Cellular respiration provides a way for all living things
to release the energy stored in food
32. Photosynthesis uses sunlight for energy.
Cellular respiration uses chemical energy (glucose)
33. Breathing is the act of physically forcing air into the
lungs. Respiration is the release of energy from food
molecules.
34. Inhalation: rib cage expands (ribs move up and out),
air taken in, diaphragm contracts and moves down,
chest cavity expands, air pressure decreases.
Exhalation: rib cage contracts, diaphragm relaxes and
moves up, chest cavity contracts, air pressure
increases.
35. Four characteristics required for a respiratory
surface:
- moist at all times
- thin
- source of oxygen
- closely connected to transport system that
delivers gases to and from cells.
36. Drifting cells in the ocean can be called the
pastures of the sea because they both carry
out photosynthesis and make organic
compounds (food) for other organisms.
37. Microscopic cells drifting in the
ocean are like land plants in that they:
a. Are the beginning of the food chain for most
other organisms
b. They release oxygen into the atmosphere
c. They bloom in the spring
38. Photographs from orbiting satellites have
improved our ability to study life in the
ocean.
Ch 7: Energy and Matter in
ecosystems
1.
2.
3.
4.
5.
6.
7.
8.
A
D
C
A
B
B
B
D
9. B
10. B
11. C
12. B
13. C
14. C
15. B
16. A
17. B
18. D
19. B
20. B
21. A
22. C
23. C
24. A
25. B
26. D
27. A
28. A
29. B
30. C
31. Biotic: living organisms
Abiotic: non-living parts: water, air, soil
32. Producers: first trophic level autotrophs
consumers: second level and up,
heterotrophs
33. A food web shows the interconnected
nature of the relationships between
organisms.
34. A pyramid is useful to show energy
relationships because the most energy is
found at the base, and each level up
decreases by about 90%, creating a
pyramid.
35. C
36. D
37. B
38. B
39. C
40. C
41. D
42. When a chemical pollutant enters the
ecosystem, it can accumulate from one
trophic level to the next. Organisms at
the bottom of the food chain have some
pollutant, but organisms at the top (who
eat many of the lower level organisms)
accumulate a great deal of pollutant
Biaccumulation of mercury in fish
LEAST MERCURY
Enjoy these fish:
Anchovies
Butterfish
Catfish
Clam
Crab (Domestic)
Herring
Mackerel
Mullet
Oyster
Perch (Ocean)
Salmon (Canned)**
Salmon (Fresh)**
Sardine
Scallop*
Shad (American)
Shrimp*
Sole (Pacific)
Squid (Calamari)
Tilapia
Trout (Freshwater)
Whitefish
MODERATE MERCURY
Eat six servings or less per month:
Bass (Striped, Black)
Carp
Cod (Alaskan)*
Croaker (White Pacific)
Halibut (Atlantic)*
Halibut (Pacific)
HIGH MERCURY
Lobster
Mahi Mahi
Eat three servings
Monkfish*
per month:
Perch (Freshwater)
Snapper*
Tuna (Canned
Bluefish
chunk light)
Grouper*
Tuna (Skipjack)*
or less
Mackerel (Spanish, Gulf)
Sea Bass (Chilean)*
Tuna (Canned Albacore)
Tuna (Yellowfin)*
43. B
44. -------------------------
45. a)producers/plants
b)(photo)autotrophs
c) photosynthesis
46. Greater biodiversity
increases the chances
that, in the event of an environmental
catastrophe, at least some organisms would
have variations that would enable them to
survive.
47. D
48. A
49. B
50. C
51. Snake – predator
mouse – prey
52. grasses: producers
rabbits: herbivores
foxes: carnivores
bacteria: decomposers
53. The amount of matter on Earth is fixed; most of the material
that is here has been here since the Earth was formed, and
gets recycled over and over. Energy is constantly being used,
and dissipated away. Earth needs a constant source of new
energy. It cannot be recycled.
54. Photosynthesis takes in carbon dioxide, and releases oxygen
as a waste product. Cellular respiration takes in oxygen, and
releases carbon dioxide as a waste product.
55. A forest ecosystem has much more diversity than a cornfield,
therefore it is more stable. Biodiversity is very important
because it ensures survival of at least some species.
56. Humans caused the current loss of biodiversity through loss
of habitat. Construction has caused loss of migration reststops; loss of food; fish that need running water to live will die
in a lake created by a dam.
57. The Everglades are known as a “river of
glass” because the vast majority of this
area is covered by a dense growth of
saw grass, through which a steady flow
of water moves.
58. Sugarcane production is one human
activity that has harmed the Everglades.
Pesticides and fertilizers, used by
farmers to increase crop yields, have
also had a harmful effect.
59. In 1996, the federal government endorsed the
everglades restoration project. They will try to
stop sugarcane production in the Everglades.
They will also try to let large areas of land act
as natural filters to remove some of the
contaminants in the water. They will also try to
restore the natural north-flow of water.
60. Peoples’ attitudes have changed toward the
Everglades in that the importance of this
ecosystem has been recognized, and people
are trying to restore its health.
Chapter 9: Classification
1.
2.
3.
4.
5.
6.
7.
8.
B (domain)
D
C
C
C
D
D
B
9. C
17. B
10. B
11. D
12. C
no 13.
14. C
15. C
16. D (domain)
18. Prokaryotes – no nucleus; no organelles
-carry out processes in their cell
membranes, simpler processes
Eukaryotes – nucleus; organelles
-carry out processes in specific
organelles, more complex
19. C
20. Leopard – hair; no organism has hair
before leopard, after it is no tail which
doesn’t describe the leopard
21. A dichotomous key asks pairs of
questions, of which only one applies to
each organism and directs you to the next
question in order to narrow down which
organism has the traits being observed.
Ex.: Leopard: Does it have hair? Or does it
not have hair?
22.Pollen is released into the wind – only
male gamete
Coral release both eggs and sperm into
the water
23. Genetic recombination = variation
24. Amount lost to predation is lessened
Chapter 10: Evolution
1.
2.
3.
4.
5.
6.
7.
8.
D
D
D
C
C
D
B
C
9. B
10. C
11. B
12. A
13. C
14. B
15. D
16. A
17. A
18. B
19. D
20. D
21. C
22. B
23. C
24. D
25. Through genetic variation and natural
selection, new species have developed which
are fit for their environment.
26. There is always competition for resources,
which means that the organisms best adapted
will survive.
27. Variations allow for new traits to develop,
which can lead to evolution of the population
28. Radiation and chemicals, and mistakes in
replication; gametes.
Body cells would not pass on their DNA to
offspring.
29. Water, food, mates. The animals with
the traits that allow them to get the
resources will survive and reproduce,
while the animals without those
adaptations will not.
30. D
31. Chromosomes from 2 parents instead of
one increase variation, as well as crossing
over and independent assortment. More
variation means more traits available in
population. Some traits will be
adaptations helping the organism survive.
32. Creates variation in a population.
33. B
34. Natural selection includes the other
three. In order for natural selection to
occur there must be competition (struggle
for existence) and variation in the
population. Also, the environment must
change in order for new traits to be
selected for.
35. In a population, some individuals get
separated and form their own population in
a different location. If the new
environment is different than the original
environment, individuals with the traits
best adapted for the new environment will
survive and reproduce. Ones without
these traits will die off. Eventually, the
new population is different enough from
the original population that they are
reproductively isolated and therefore a
new species.
36. The bacteria that had some immunity to the
antibiotic survived and reproduced and
eventually the population became large enough
to make the patient sick again.
37. B
38. Adaptation: trait that helps an organism survive
in its environment; Speed of cheetahs. Can
chase down its prey.
39. Some insects had the genes to be resistant to
the pesticide. They survived and reproduced.
Eventually the entire population had the genes
to resist the pesticide.
40. Good news: cures bacterial infections
Bad news: Overuse causes antibiotic
resistant strains of bacteria
41. Because it is causing strains of bacteria to
evolve which are resistant to most commonly
used antibiotics. Also, those resistant bacteria
may be found in the food.
42. Natural selection explains that the overuse of
antibiotics causes the resistant bacteria to be
selected for and to reproduce causing more
dangerous infections.
Chapter 11 Evidence for Evolution
1.
2.
3.
4.
5.
6.
D
A
A
C
C
C
7. A
8. D
9. C
10. A
11. A family tree, like an evolutionary
tree, can shows ancestral
relationships.
12. Fossils are usually formed when
sediments bury an organism, and their
remains (hard tissues)are gradually
replaced by minerals. Or, the body of a
plant or animal can form an impression
in soft clay or mud, which hardens.
13. Similarities in the biochemistry of
proteins can be useful in determining
evolutionary relationships because by
studying amino acid sequences
scientists have learned that small
differences show a close relationship.
14. B
15. An “evolutionary bush” would be a better way
to diagram an evolutionary path because there
is rarely a straight lineage. Organisms often
evolve differently, as in the adaptive radiation
of the Galapagos finches.
16. C
17. A vestigial structure suggests that an ancestor
having the structure would have used it. ie.
Appendix
18. D
19. Natural selection would explain the change in
percentage of each color moth. As the
environment changed, different colors would
be selected (eaten).
20. C
21. Galapagos finches moved to different islands, with
different climates and food supplies. Individuals
having traits that were helpful to each particular
environment survived and reproduced.
22. B
23. B
24. DNA nucleotide sequence is important all organisms
store genetic information in DNA. The similarities in
DNA sequences show close relationships.
25. Mitochondrial DNA comes only from your mother.
26. Scientists have used mtDNA to study the origins of
human history.
27. Mitochondrial Eve has been shown to be the ancestor
of all humans alive today, but scientists differ on her
age. Mungo man has no mtDNA relationship to
Mitochondrial Eve, which has raised new questions
about human origins.
Chap 12: Mechanisms of Evolution
1.
2.
3.
4.
5.
6.
7.
A
B
C
A
B
B
D
8. D
9. C
10. B
11. D
12. D
13. C
14. A
15. Evolution happens in response to changes in the
environment, so since the environment is always
changing, evolution is ongoing.
16. B
17. The adaptive value is determined by how helpful an
adaptation is to survival. For example, blond hair is a
variation that has no particular survival value, unless
you happened to live in Nazi Germany.
18. Penguins that had the characteristic of liking to huddle
together would tend to live longer and produce more
offspring, who would also probably have the trait.
Over time, most penguins have this behavior.
19. See # 18.
20. A
21. C
22.
23.
24.
25.
26.
C
C
A
B
Organisms having variations that help them
survive will survive and pass on their traits to
the next generation. If environmental
conditions change, organisms having helpful
traits will survive, and over time the species
will change. Environmental changes are
usually gradual. However, if the changes are
in the nature of a catastrophe, such as a
meteorite or flood, there is not enough time for
any evolution to occur. For example, the
wooly mammoths died because there was no
food.
27. Farmers do not like prairie dogs because
they interfere with the planting of crops.
Ranchers don’t like them because their
tunnels could cause grazing animals to
fall and break legs. Black-footed ferrets
eat prairie dogs, but when prairie dogs
are poisoned, the ferrets die too.
28. In 1987 scientists captured the 18 ferrets
to breed them and re-populate the area.
29. If prairie dogs are protected, there will be
a poison-free source of food for ferrets.
Chap 13: DNA and heredity
1.
2.
3.
4.
5.
6.
7.
B
D
B
C
C
D
C
8. B
9. B (D)
10. B
11. A
12. A
13. C
14. D
15. A
16. B
17. C
18. A
19. B
20. D
21. To do its job, genetic material must be
* able to store enough information to
make another organism
* able to make a copy of itself again and
again
* strong and stable enough to not fall
apart easily
* able to mutate slightly from time to
time to provide variations
22. Cytosine and guanine pair together
Adenine and Thymine pair together
23. Crick & Watson described the basic structure
of DNA as a double helix; the double strand is
like a ladder, with nucleotide bases forming the
rungs, and sugar and phosphate groups
forming the sides.
24. Because DNA is made of only 4 different
nucleotides, it was thought to be too simple to
contain the code of life. But using the 4
different letters to make long sequences,
nature can create an almost unlimited variety
of genetic messages.
25. C
26. D
27. Genetic information is coded in the DNA
“alphabet.” The sequence of nucleotides
determines subunits called amino acids;
the amino acid sequence determines the
protein; the protein determines the trait.
28. B
29. C
30. C
31. T A A C T G G C
32. B
33. DNA is an important molecule because it
carries on life itself; all life is dependent
upon it.
34. DNA nucleotides separate and act as
templates in replication.
35. DNA molecules replicate by unwinding
and acting as a template. Enzymes help
match up free-floating nucleotides with
their appropriate complementary
nucleotides on the template. Identical
new strands are formed and then
released.
36. Box A should be a nucleotide (or nucleic
acids), which acts as a template because
it can only pair with one other
(complementary) nucleotide.
37. B proteins
38. Mutations can be helpful, as in the ability
to resist a disease, or harmful, as in loss
of some ability.
39. Scientists originally thought repetitive
DNA was “junk” because they did not
understand its functions.
40. C
41. Telomeres are of interest because they
may control the lifespan of a cell.
42. When a telomere gets very short the
cells stop dividing.
43. The enzyme telomerase can reverse the
shortening process by adding more
telomeres.
44. There is great interest in the enzyme
telomerase because it may have to do
with cancer.
45. There is great interest in the absence of
telomerase because it may have to do
with aging.
Chapter 14: Genes and protein
synthesis
1.
2.
3.
4.
5.
6.
7.
8.
B
A
C
B
C
B
D
C
9.
10.
11.
12.
13.
14.
15.
16.
C
A
A
D
A
A
D
C
17.
18.
19.
20.
D
C
B
C
21. The sequence determines the protein
and protein structure. If the structure is
changed, the function will most likely also
be changed.
22. A
23. The one change can change the shape
of the molecule and therefore make it
unable to bind to oxygen
24. Both are made up of subunits; both coil
up in specific shapes; both have a limited
number of subunits to work with
25. Since protein is made in the ribosome and
DNA is kept in the nucleus, the problem is how
can DNA control the making of protein; mRNA
solves this by copying the DNA code and
bringing it to the ribosome
26. Cell – nucleus – chromosome – gene – DNA
molecule
27. In both replication and transcription, the DNA
double helix is unwound; New subunits of DNA
or RNA are matched to the complementary
original strand according to the base sequence
of the original strand of DNA. Both processes
are controlled by enzymes
28. There are only 4 different bases and 20
amino acids, so a grouping of 3 a.a.s is
needed to be able to code for all the
necessary a.a.s and the start, stop
codes.
29. Ribosomes provide a site for the mRNA
and the tRNA to meet up an bond a.a.s
to each other.
30. Met-Cys-Val-Cys-Pro
31. Met-Try-Val-Cys-Pro
32. Since GGT and GGG both code for
Proline, there is no effect
33. DNA double helix opens up and unwinds;
RNA subunits match up with DNA
subunits; a new RNA molecule moves
out through the pores; RNA base
sequences translate into a.a. sequences
34. C
35. mRNA copies DNA base sequences and
moves to ribosome; tRNA carries a.a.s to
ribosome and matches its anticodons to
mRNA codons in order to place a.a.s in
correct order in protein chain.
36. All organisms have ATCG DNA molecules.
This is significant because is shows that all
organisms have inherited their DNA from
previous organisms. Mutations is DNA have
resulted in the diversity of organisms we have
today.
37. A mutation could cause a different a.a. to be
placed in the protein, thereby making it
different from the intended protein
38. (a) These two cells are in different parts of the
body and express different genes causing
them to perform different functions
(b) these cells do not make the same proteins
(c) Yes, they have the same DNA
39. That humans have only ~35,000 genes
40. Protein shapes have been shuffled
around during evolution creating much
complexity among living organisms
41. Each gene does not control one trait,
usually each gene interacts with a few
others to produce a trait.
Chapter 15: Asexual reproduction
and Mitosis
1.
2.
3.
4.
5.
6.
7.
8.
B
C
A
D
A
B
A
C
9.
10.
11.
12.
13.
14.
15.
16.
B
B
D
C
B
A
A
C
17.
18.
19.
20.
21.
D
C
C
B
C
22. One individual not reproducing due to a
shortened life span will not affect a
species. However, if the entire
population does not reproduce due to
shortened lifespans, then the species will
decrease in size and it could lead to
extinction
23. Genetic material is used to direct how
the cell is made and how the cell
functions
24. Cell growth > Replication > Mitosis > Cell
division
25. B
26. Each species has a specific number of
chromosomes that varies from species to
species
27. Since one cell is dividing into two. Two
copies of each chromosome are needed,
so each daughter cell gets exactly the
same DNA as the parent cell
28. Cell division is necessary for singlecelled organisms in order for them to
reproduce; amoeba divides by binary
fission to make two new amoeba
Cell division is necessary for multicellular organisms in order for them to
grow; a zygote grows into a fully formed
baby through cell division
29. Mitosis is the dividing of the
chromosomes and it occurs first;
cytokinesis is the dividing of the
cytoplasm and it occurs last
30. B
31. Both result in 2 cells which are
genetically identical; binary fission results
in 2 equally sized daughter cells, while
budding results in one large parent cell
and one small daughter cell
32. B
33. Yes; red blood cells reproduce quickly
since they are needed to carry oxygen to
other cells to keep organism alive
34. Exposure to these mutagens can mutate
(change) the DNA. Once this happens the cell
may not be able to make the proteins to control
cell growth and these cells reproduce
uncontrollably; cancer
35. Lymph and circulatory systems both involve
tubes throughout the body. Lymphatic system
carries lymph(fluid); circulatory carries blood.
Lymph drains into circulatory.
36. Chemotherapy attacks DNA of cancer cells; or
shuts down protein synthesis of cancer cells or
stimulates immune system against cancer cells
37. Targeted drugs are specific for the
cancer cells, attack only cancer cells
Ch 16: Sexual reproduction and
meiosis
1.
2.
3.
4.
5.
6.
7.
8.
A
B
B
C
D
D
B
B
9. C
10. C
11. D
12. A
13. D
14. C
15. B
16. A
17. C
18. C
19. D
20. C
21. D
22. B
23. Chromosomes contain the inherited (genetic)
information that has been passed along since
the beginning of life. They contain the
information that determines an individual’s
characteristics.
24. Sexual reproduction is “all about the
chromosomes” because when a sperm cell and
an egg cell unite during sexual reproduction, the
two nuclei join. Each nucleus contains
chromosomes.
25. In the process of sexual reproduction, the nuclei
of gametes (sex cells) join together in fertilization
to form a zygote (fertilized egg cell).
26. Gametes are essential to sexual reproduction because they
contain half of the normal number of chromosomes. When
fertilization occurs, the normal number of chromosomes is
restored.
27. Without fertilization (process 2) neither eggs nor sperm are
viable, they to join to get the full set of chromosomes.
28. The eggs in process 1 have undergone meiosis and have a
half set of chromosomes.
The eggs in process 3 have been fertilized and have the full
set of chromosomes, and have begun to grow (mitosis).
29. A mutation in a gamete will affect the whole new organism,
because that change will be copied as each cell undergoes
mitosis. A change in a body cell will only be copied by that
one body cell, which will affect a very small area of the
body.
30. Sexual reproduction in any form involves
creating new genetic combinations by joining
chromosomes from both parents. This
increases diversity in a species, which
increases chances for the survival of the
species.
31. Mitosis produces 2 identical daughter cells,
each of which has 2 full sets of chromosomes.
Meiosis produces 4 daughter cells, each with a
half-set of chromosomes.
32. C
33. C
34. C
35. A
36. Organisms
that reproduce sexually are not genetically identical to their
parents because they get half of their genes from each parent. In
addition, during meiosis some crossing-over may take place, further
increasing differences.
37. Asexual reproduction
Sexual reproduction
offspring genetically identical
offspring genetically different
no exchange of genetic material
exchange of genetic material
division of parent cell
2 parents, produce gametes
38.
Crossing-over is occuring. The chromosomes in step C are have
different alleles on them.
38.
The offspring will have different combinations of genes than the parents.
38.
In flowering plants, male and female gametes join to produce a zygote.
This takes place in the flower. The zygote grows into an embryo, and
later an adult plants.
41. C
42. C
43. Some species must lay hundreds of eggs
in order for some to survive because
most of the eggs will be eaten by a
carnivore.
44. Fertilization must be internal for the
sperm to swim to the egg.
45. Joseph’s doctor ordered tests because
he was not developing normally.
46. Due an error that may have occurred
during meiosis, Joseph inherited an extra
X chromosome.
47. They learned the explanation for his
condition, and that he could look forward
to a normal life, and the options for
having a family.
Ch 17: Patterns of Inheritance
1.
2.
3.
4.
5.
6.
7.
D
B
A
C
B
B
D
8. C
9. A
10. C
11. D
12. C
13. B
14. B
15. B
16. A
17. C
18. D
19. A
20. D
21. B
22. A
23. B
24. C
25. D
26. D
27. Mendel is called the “founder” of genetics
because he is the first to begin a real
study of inheritance and the way it works.
28. Mendel noticed that a trait, or hereditary
information, is passed from parents to
offspring in individual units that he called
factors.
29. B
30. D
31. A
32. Fur color in Siamese cats illustrates how the expression
of genes can be affected by the environment. The gene
that codes for the enzyme that produces dark fur only
works at cool temperatures. This could be adaptive in
that cats living in cooler climates could benefit from the
absorption of extra warmth of dark colors.
33. C
34. Hemophilia occurs more frequently in males than
females because it is a sex-linked trait. This means that
the gene for hemophilia is on the
X chromosome. If a female has it
on one of her 2 X chromosomes,
she is usually a normal, dominant
X
Y
allele on the other chromosome.
Xh XhX XhY
However, in males there is no
second allele, so the gene will
be expressed.
X
XhX XY
35. Humans have influenced the genetic makeup
of organisms by selective breeding or artificial
selection. This has been done to grow crops
that can grow more plentifully, are resistant to
diseases, and look and taste better. They
have also bred animals that have thicker wool,
lay larger eggs, produce more milk, run faster,
or perform tasks.
36. People that carry out specific genetic crosses
must use organisms that reproduce sexually
because asexual reproduction involves no
exchange of gametes from different parents.
37. John Loraine 1812
George H Shull
Edward East and
Donald Jones 1917
Crossed 2 different
strains of corn, and
made a hybrid that
produced a greater
yield than either
parent.
Increased corn yields
by 25-50%
Combined 2 different
hybrid varieties to
produce a highly
productive variety
that could be grown
commercially
38. Super corn has spread unintentionally,
mixing with native corn
39. The study of genetics has provided us
with a food crop that is a staple of our
diet, and makes more and better food for
people all over.