THIS IS NOT THE EXAM REVIEW SHEET!
HELLO EVERYONE!!! These are questions
from old exams that are relavent to Exam 4. I
understand that there are many... however, these
are an INCREDIBLY HELPFUL resource. I
highly recommend running through all of them
(maybe try answering 25-50 per day?) These
questions are directly copied and pasted from a
folder on blackboard posted by your professors.
Digestion, Transport and cardiovascular
systems
1. Which of the following does NOT require
hemoglobin to deliver oxygen to the tissues.
a. Earthworms
*b. Insects
c. Mammals
d. Birds
e. Amphibians
2. The vessels that return blood to the heart in a
closed circulatory system are referred to as
a. arteries.
*b. veins.
c. capillaries.
d. sinuses.
e. auxiliary hearts.
3. Which of the following is NOT a component
of vertebrate blood?
a. plasma.
b. leukocytes.
c. erythrocytes.
d. platelets.
*e. myoglobin.
4. Hemoglobin is more likely to release oxygen
in metabolically active tissues because
a. Metabolically active tissues produce more
hemoglobin
b. Metabolically active cells are nearer to
capillaries
*c. CO2 is an allosteric regulator of hemoglobin
d. CO2 competes for heme binding
e. Endorphins released by active tissues trigger
oxygen release
5. In Tibetan populations living at high
elevations, blood oxygen saturation levels have
been correlated with
a. Rates of pregnancy
b. Rates of live birth
c. Gestation period
*d. Infant mortality
e. Premature menopause
6. What allows many marine invertebrates (e.g.
corals, jellyfish, sea anemones) to grow large in
size even though they have only a gastrovascular
cavity for circulation?
*a. these organisms are only a few cells thick
and can rely on diffusion to transport nutrients
and oxygen throughout the body
b. there are many branches within the
gastrovascular cavity that directly transport
nutrients and oxygen to various tissues
c. a single, large heart provides enough pressure
to deliver the blood throughout the entire body
d. there are many openings to the gastrovascular
cavity that allow nutrients and oxygen to be
taken up from all directions
7. Why are respiratory and circulatory systems
tightly coupled in organisms with closed
circulatory systems?
a. all cells in the body require nutrients, oxygen,
and waste removal
b. organisms with a low surface area:volume
ratio cannot only rely on the simple diffusion of
nutrients and gases to sustain life
c. if these systems weren’t coupled, the blood
pressure would be too low to circulate the blood
throughout the entire body
d. all of the above are true
*e. only A and B are true
8. Cooperative binding of O2 by hemoglobin is
physiologically important because
a. it overcomes the limitation imposed by
diffusion rates
b. it allows saturation of blood with O2 at low
partial pressure
*c. it allows hemoglobin to readily give up most
of its oxygen at sites of physiological activity
d. it increases the O2 carrying capacity of blood
e. it allows efficient exchange of O2 for CO2
9. Plant gas exchange occurs mainly through
which of the following structures?
a. companion cells
b. trachea
c. alveoli
*d. stomata
e. vessels
10. Consider the graphs shown. The center, blue
line represents the O2 dissociation curve for
adult hemoglobin. The line that represents fetal
hemoglobin is
a. A because adult hemoglobin has a higher
affinity than fetal Hb for O2
*b. A because fetal hemoglobin has a higher
affinity than adult Hb for O2
c. B because adult hemoglobin has a higher
affinity than fetal Hb for O2
d. B because fetal hemoglobin has a higher
affinity than adult Hb for O2
11. Which of the following factors contribute to
water flow in xylem?
*a. active transport in root cells and
evapotranspiration through stomates
b. root peristalsis and evapotranspiration through
stomates
c. active transport in root cells and capillary
action
d. capillary action and evapotranspiration
through stomates
e. active transport in root cells and capillary
action
12. What is an advantage for insects to have an
open circulatory system rather than a
gastrovascular cavity?
a. Insects are more efficient with a single heart.
*b. Insects are terrestrial.
c. Open circulatory systems allow high
hemolymph pressures.
d. An open circulatory system allows coupling
of respiratory and circulatory systems.
13. What is an advantage for insects to have an
open circulatory system rather than a
gastrovascular cavity?
*a. An open circulatory system provides for
more metabolic dynamic range; the animal can
respond to changes in energy demands.
b. Insects don’t have open circulatory systems.
c. Open circulatory systems allow high
hemolymph pressures.
d. An open circulatory system allows coupling
of respiratory and circulatory systems.
14. Which of the following statements about
amphibian and mammalian circulatory systems
is true?
*a. Pulmonary circulation occurs at reduced
blood pressure.
b. Amphibians have 4 heart chambers similar to
mammals.
c. Oxygen and carbon dioxide exchange only
occursin the lungs and skin.
d. All of the above are true.
e. None of the above are true.
15.
Which of the following statements is NOT true
about a capillary bed?
a. The drop in blood pressure across the
capillary is partially due to fluid loss.
*b. Large proteins diffuse out of the vasculature
on the arteriole side and intothe vasculature on
the on the venule side.
c. The lymphatic system collects water and
solutes that are not picked up by the venules.
d. The addition of CO2 to the blood decreases
the pH of the blood.
e. None of the above. All of the above
statements are true.
16. Which of the following statements about the
blood vessels shown in this figure is NOT true?
a. The endothelium provides the conduit for the
transport of the blood while allowing small
molecules to diffuse into and out of the
circulatory system.
b. The elastic layers of the large arteries and
large veins help to moderate blood pressure
fluctuations during and between heart
contractions.
c. Fenestrated capillaries allow more fluid loss
than continuous capillaries.
d. The smooth muscle cells contribute to
vasodilation and vasoconstriction.
*e. None of the above. All of the statements are
true.
18. This question focuses on long-distance
transport in the xylem. Which of the following is
NOT true?
*a. Flow of fluids through xylem is not mediated
by pressure differences.
b. Cohesion-tension theory relies on the polar
nature of water molecules.
c. Transpiration involves evaporative loss of
water.
d. None of the above. All of these statements are
true.
(No figure...)
19. The figure above is from your textbook.
Which of the following statements is NOT true?
a. Osmosis is a key component of water flow
between the xylem and the phloem.
*b. Developing fruit represents a sucrose source.
c. Sink cells uptake sucrose by means of
plasmodesmata and concentration gradients.
d. Source cells have higher osmotic pressure
than sink cells.
e. None of the above. All of these statements are
true.
20. Stomatal opening is driven by….
a. Water efflux from the guard cells driven by
osmosis due to lower extracellular ion
concentrations.
*b. Water influx via osmosis into the guard cells
due to pumping of ions and cotransport of sugars
into the guard cells.
17. Based on what is shown in these oxygen
binding curves, which of the following is true?
a. At lower temperatures hemoglobin has a
lower affinity for oxygen.
b. Elevated temperatures increase hemoglobin’s
affinity for oxygen.
c. Increasing exertion at higher altitudes
increases oxygen binding to hemoglobin.
d. All of the above are true.
*e. None of the above are true.
21. What energy sources drive water transport in
the xylem?
a. Gravity and photosynthesis
b. Stomates and soil pressure
c. Gas exchange and xylem vessels
*d. Sunlight and ATP
22. Where to roots get their sugars?
a. From photosynthesis in the root hairs
*b. Via the phloem from the leaves
c. By active transport from the soil
23. Which of the following is NOT an important
aspect contributing to water transport through
the xylem?
a. cohesion among H2O molecules due to
hydrogen bonding
*b. osmosis due to sugar produced in
photosynthesizing leaves
c. active transport of mineral ions from the soil
into roots
d. transpirational H2O loss from leaves
e. continuous tubes created by dead vessel and
tracheid cells
24. Consider the graphs shown. The center, blue
line represents the O2 dissociation curve for
hemoglobin under normal physiological
conditions. The line that represents hemoglobin
(Hb) in tissues undergoing intense metabolic
demands is
a. A because CO2, low pH and high
temperatures increase the affinity of Hb for O2
b. A because CO2, low pH and high
temperatures decrease the affinity of Hb for O2
c. B because CO2, low pH and high
temperatures increase the affinity of Hb for O2
*d. B because CO2, low pH and high
temperatures decrease the affinity of Hb for O2
Nervous System
25. Which of the following cells or structures is
part of the peripheral nervous system?
a. an interneuron in your brain
b. the spinal cord
*c. the cell body of a sensory neuron on your
tongue
d. the hypothalamus
e. an intestinal epithelial cell
26. A rattlesnake just tried to bite you. Your
pulse is racing and you notice your pupils are
wide open when you step into your car and look
in your rearview mirror. What part of your
autonomic nervous system is activated?
a. Myelencephalon
b. Neocortex
*c. Sympathetic
d. Peripheral
e. Parasympathetic
27. As an action potential moves along an axon,
the membrane potential changes. Which of the
following best describes the molecular
mechanisms that cause these changes in
membrane potential?
a. Action potentials are mediated by changes in
transcription. Different gene expression patterns
cause different membrane potentials.
b. As an electron moves along the length of the
axon, it transiently heats the membrane, and this
changes the membrane potential.
c. Action potentials are mediated by calciummediated exocytosis of neurotransmitters. When
the vesicles fuse with the membrane, this
changes the membrane potential.
d. Sodium and potassium ions speed along the
length of the axonal cytoplasm, and this changes
the local membrane potential as the action
potential passes through.
*e. Action potentials are mediated by voltagegated sodium and potassium channels, and
diffusion of ions across the membrane cause the
changes in membrane potential.
28. The location for chemical communication
between a neuron and a target cell is called the
a. motor neuron
*b. synaptic cleft
c. oligodendrocyte
d. acetylcholine
e. axon hillock
29. In a neuron, the nucleus is located in the
a. dendritic region.
b. axon hillock.
c. axon.
*d. cell body.
e. axon terminals.
30. In a neuron, the nucleus is located in the
a. dendritic region.
b. axon hillock.
c. axon.
*d. soma.
e. axon terminals.
31. In general, the input processes of a neuron in
the central nervous system are referred to as
a. axons
b. synaptic cleft
c. neuromuscular junction
*d. dendrites
e. synaptic terminals
37. Which of the following changes would result
in depolarization of the membrane?
*a. Na+ entering the cell
b. K+ leaving the cell
c. Retraction of the axon
d. Neurotransmitter release from the cell
32. Which of the terms below best describes
neurons that make local connections between
neurons in the brain?
a. motor neurons
b. sensory neurons
*c. interneurons
d. hub neurons
e. transit neurons
33. Which term below best describes neurons
that are responsible for stimulating contraction
of muscles in your leg?
*a. motor neurons
b. sensory neurons
c. interneurons
d. hub neurons
e. transit neurons
34. Which term below best describes neurons
that are responsible for sensing pressure in your
skin?
a. motor neurons
*b. sensory neurons
c. interneurons
d. hub neurons
e. transit neurons
35. Which is NOT a factor that contributes to the
resting potential?
a. Ion specific channels allowing passive
movement of ions
b. Na+/K+ -ATPase
*c. Binding of neurotransmitters to ligand-gated
ion channels
d. Negatively charged molecules such as
proteins that are more abundant inside the cell
e. All the above contribute to the resting
potential
36. The inside of a plasma membrane of a
neuronal axon generally has a negative resting
potential relative to the outside of the cell. 37.
38. In the two cellular compartments shown
above, K+ is moving across the membrane from
the left to the right. Why is K+ moving from the
left to the right?
*a. K+ is moving down its concentration
gradient
b. K+ is moving down its electrical gradient
c. Cl- is attracting K+
d. K+ is moving because the membrane is
impermeable to Cl-
39. If the K+ channel closed, so the ions were
trapped in the compartments as shown above,
what would the voltage of the right side of the
cell be in relation to the left?
*a. Equal
b. Negative
c. Positive
d. Cannot be determined
40. The response of a postsynaptic cell is
determined by:
a. A. The type of neurotransmitter released at the
synapse.
b. B. The type of receptors the postsynaptic cell
has.
c. C. The number of Na+ channels in the
postsynaptic membrane
d. D. The number of K+ channels in the
postsynaptic membrane.
*e. All of the above
f. A and C only
41. How does a sensory system provide
information about the intensity of a stimulus?
a. The larger the action potential, the larger the
stimulus.
b. by the release of both dopamine and
acetylcholine the cell senses a larger stimulus
c. More chloride channels close, thereby
creating greater transmitter uptake.
*d. Via action potentials, the frequency of action
potential firing is related to the intensity of the
stimulus.
42. How does a sensory system provide
information about the intensity of a stimulus?
a. The higher the threshold, the larger the
stimulus.
b. by the release of both dopamine and
acetylcholine the cell senses a larger stimulus
c. More chloride channels close, thereby
creating greater transmitter uptake.
*d. Via action potentials, the frequency of action
potential firing is related to the intensity of the
stimulus.
43. The process whereby incoming sensory
information is converted to an electrical signal is
known as:
a. threshold potential
b. an action potential
c. perception
*d. sensory transduction
e. reception
44. As a sensory neuron in your skin is lightly
stimulated, a receptor potential is generated.
However, the membrane potential change in this
sensory neuron does not reach threshold. Most
likely, you perceived that stimulus as a sensation
of:
a. pain
b. heat
c. cold
d. intense pressure
*e. I did not perceive that, since the threshold
potential was not achieved, I could not perceive
that sensation.
45. What type of stimulus is responsible for
activating your cones and rods?
a. mechanical energy
b. thermal energy
c. chemical energy
*d. electromagnetic energy
e. pressure energy
46. Touch receptors in your skin are activated by
what type of stimulus?
a. electromagnetic energy
b. nuclear energy
*c. mechanical energy
d. photonic energy
e. sonic energy
47. How do neurons establish differential
concentrations of ions inside and outside the
cell?
*a. active transport
b. osmosis
c. simple diffusion
d. facilitated diffusion
48 . What factors contribute to the resting
potential in a nerve cell?
a. sodium-potassium pumps, ligand-gated ion
channels, negatively charged molecules (i.e.
proteins) are more abundant inside the cells
b. sodium-potassium pumps, ion specific
channels, positively charged molecules (i.e.
proteins) are more abundant inside the cells
*c. sodium-potassium pumps, ion specific
channels, negatively charged molecules (i.e.
proteins) are more abundant inside the cells
d. sodium-potassium pumps, ion specific
channels, positively charged molecules (i.e.
proteins) are more abundant outside the cells
49. Initiation of an action potential involves:
a. membrane hyperpolarization
*b. Sodium channel opening
c. Potassium channel opening
d. refractory period
e. Potassium channel closing
54. In some plants electrical signals can travel
from cell to cell via:
a. electrical synapses
b. tight junctions
c. chloroplast synapses
*d. plasmodesmata
50. In an action potential, the return to the
resting potential involves:
a. A. Cl- channel inactivation
b. B. Na+ channel inactivation
c. C. Na+ channel opening
d. D. K+ channel closing
e. E. K+ channel opening
f. A, B and D
g. B and D
*h. B and E
55. In some plants electrical signals can travel
from cell to cell via:
a. gap junctions
b. ligand-gated ion channels
*c. plasmodesmata
d. chloroplasts
51. Which of the following features allow
neurons to rapidly conduct action potentials to
muscles in your foot?
(1) myelination of the axon provided by
oligodendrocytes
(2) a large diameter axon
(3) a small, narrow diameter axon
(4) myelination of the axon provided by
Schwann cells
a. 1 and 2
b. 1 and 3
*c. 2 and 4
d. 3 and 4
52. How does our nervous system organize
information about our sensory environment?
a. by opening more voltage-gated and ligandgated ion channels
*b. by forming topographic representations of
that particular sensory information
c. by relaying information using interneurons
through the spinal cord
d. by increasing the amplitude of the receptor
potentials
53. In some plants electrical signals can travel
from cell to cell via:
a. electrical synapses
b. chemical synapses
c. chloroplast junctions
*d. plasmodesmata
56. Why are squid giant axons used in
neuroscience research?
a. their action potentials are stronger and hence
easier to detect.
b. they do not have any refractory period and so
can be used repeatedly.
*c. they have a large diameter and so can be
easily impaled by electrodes to record their
membrane potential.
d. because squid live in saltwater their axons can
be easily kept alive in a saline solution.
57. In a resting neuron, the concentration of
potassium ions (K+) is:
*a. higher inside the cell than outside of the cell
b. lower inside the cell than outside of the cell
c. the same inside and outside the cell
d. it varies with different neurons
58. In a resting neuron, the concentration of
sodium ions (Na+) is:
a. higher inside the cell than outside of the cell
*b. lower inside the cell than outside of the cell
c. the same inside and outside the cell
d. it varies with different neurons
59.Which of the following factors contribute to
the resting potential in a nerve cell?
a. Ion specific channels that allow passive
movement of ions
b. An ATPase-driven sodium-potassium ion
pump.
c. Negatively charged molecules such as
proteins that are more abundant inside the cell.
*d. All the above contribute to the resting
potential
60. Which is involved in repolarizing a neuronal
membrane following an action potential?
a. Vesicle fusion
b. Ligand gated channels
*c. Opening K+ channels
d. Opening Na+ channels
61. Which is involved in depolarizing a neuronal
membrane during an action potential?
a. Vesicle fusion
b. Ligand gated channels
c. Opening K+ channels
*d. Opening Na+ channels
62. In an action potential, the return to the
resting potential involves:
a. Na+ channel opening and K+ channel closing
b. Ca+ binds to vessicles to induce exocytosis
*c. Na+ channel inactivation and K+ channel
opening
d. None of the above.
63. What do potassium ions (K+) do during an
action potential?
a. they exit the neuron via vesicle exocytosis.
b. they bind to vesicles to induce exocytosis.
*c. they exit the neuron via voltage-gated
potassium channels.
d. they exit the neuron via the sodium-potassium
pump.
64.What do sodium ions (Na+) do during an
action potential?
a. they enter the neuron via sodium-potassium
pumps and depolarize the membrane.
*b. they exit the neuron through voltage-gated
sodium channels and hyperpolarize the
membrane.
c. they enter the neuron via voltage-gated
sodium channels and depolarize the membrane.
d. they enter the synaptic cleft via exocytosis.
65.Which of the following statements about
graded potentials in neuronal signaling is NOT
TRUE?
a. They sometimes involve membrane
hyperpolarization
b. They sometimes involve membrane
depolarization
c. They vary in amplitude according to the
strength of a stimulus
d. They determine whether threshold potential is
reached for initiating an action potential
*e. All of the above statements are true
66. Action potentials are normally conducted in
just one direction on an axon because
a. voltage gates prevent back conductance
*b. Na+ channels are inactivated during the
refractory period
c. myelin sheaths provide directional guidance
d. there is an electrochemical gradient toward
the end of the axon
e. all of the above
67. If you artificially depolarize the membrane
to start an action potential in the middle of an
axon, what will happen?
a. Nothing. Action potentials can only initiate at
the axon hillock.
b. The action potential will be conducted in just
one direction (toward the synapse).
*c. The action potential will travel in both
directions.
d. The neuron will die.
68. Myelination of axons is important because
a. it slows the speed of neural impulse
conductance
b. it enhances neurotransmitter sensitivity
*c. it enhances the speed of neural impulse
conductance
d. it increases the strength of action potentials
e. it lowers threshold potential
69. Individuals with multiple sclerosis have
longer reaction times to various stimuli. This can
be explained by the following:
a. They have a defect in voltage-gated sodium
channels which are required to initiate action
potentials.
*b. They have degradation of myelin sheaths
resulting in slower conductance of signals.
c. They have a defect in neurotransmitter
release, so it takes a longer time to transmit
sufficient numbers of graded potentials to the
post-synaptic cell.
d. They have abnormal ladder-like connections
in their cerebral cortex, resulting in impaired
decision-making ability.
70. Which of the following statements about
myelin sheaths on axons is NOT TRUE
*a. They are secreted by the nodes of Ranvier
b. They are composed of layers of glial cell
membranes wrapped around the axon
c. They produce saltatory neural signal
conductance
d. They increase the speed of neural signal
conductance
e. All these statements are true
e. direct chemotaxis of axons to guide neural
connections during development
75. Presynaptic release of neurotransmitter
a. Is triggered by a graded potential
b. Occurs through gap junctions
c. Requires electrical synapses
d. Occurs via endocytosis
*e. Occurs via exocytosis
71. A neurotransmitter is
*a. a signaling molecule that influences
membrane potential of a post-synaptic cell
b. an electro-chemical impulse
c. a type of glial cell
d. a type of membrane vesicle
e. a gap junction that connects two neurons
76. Predict the effect of a chemical that blocked
voltage-dependent Calcium ion channels at the
synaptic ending of an axon.
a. The axon could not generate an action
potential.
b. The cell would continually release
neurotransmitter via vesicle exocytosis.
*c. The calcium channels would not open, and
this would inhibit neurotransmitter release.
d. It would not have an effect. Only sodium and
potassium channels are voltage-gated; Calcium
channels are ligand-gated.
72. A neurotransmitter
*a. is a signaling molecule that influences
membrane potential of a post-synaptic cell
b. is an axon
c. is an electrical impulse
d. is a type of membrane vesicle
e. is a type of efferent motor neuron
77. A neurotoxin that stimulated acetylcholine
release would most likely cause
a. numbness
b. hallucinations
c. ATP depletion
*d. muscle cramping
e. dizziness
73. Postsynaptic cells
a. Receive signals by endocytosis
b. Always respond to signals with an action
potential
c. Are always neurons
*d. Often contain neurotransmitter receptors
e. Are connected to presynaptic cells by gap
junctions
78. The peripheral nervous system
a. Controls cognition
*b. Provides sensory input
c. Commands the central nervous system
d. All of the above
74. In neural signaling, ligand-gated ion
channels
*a. are ion channels that are opened (or closed)
in response to binding a neurotransmitter
b. are gap junctions that allow Na+ transport
across a synapse
c. are voltage-gated Ca++ channels that trigger
neurotransmitter uptake
d. are sensory neurons that detect
electromagnetic stimuli
79. Approximately how long does a single
action potential take?
*a. 3 milliseconds
b. 30 microseconds
c. 180 milliseconds
d. 250 milliseconds
80. Approximately what is the normal resting
potential of a neuron?
a. -100 mV
*b. -70 mV
c. -30 mV
d. 30 mV
81. Approximately how many neurons do you
have in your brain?
a. 100 million
b. 1 billion
c. 10 billion
*d. 100 billion
82. Which lobe of the brain is most responsible
for vision?
a. Parietal lobe
*b. Occipital lobe
c. Temporal lobe
d. Frontal lobe
83. Which lobe of the brain is most responsible
for conscious thought?
a. Parietal lobe
b. Occipital lobe
c. Temporal lobe
*d. Frontal lobe
84. Which of the following is most highly
developed in human brains compared to other
mammals?
a. Medulla oblongata
b. Hypothalmus
*c. Cerebral cortex
d. Midbrain
e. Hindbrain
85. How does a sensory system provide
information about the intensity of a stimulus?
*a. Sensory receptors produce different
frequency of action potentials depending on
intensity of a stimulus
b. Sensory receptors produce different amplitude
of action potentials depending on intensity of a
stimulus
c. By the release of both dopamine and
acetylcholine the cell senses a larger stimulus
d. More chloride channels close, thereby
creating greater transmitter uptake.
86. How does a sensory system provide
information about the intensity of a stimulus?
a. The stronger the action potential, the more
intense is the stimulus.
b. by the release of both dopamine and
acetylcholine the cell senses a larger stimulus
c. More chloride channels close, thereby
creating greater transmitter uptake.
*d. The frequency of action potential firing is
related to the intensity of the stimulus.
87. One type of mechanosensors
a. Responds to chemical pheromones released by
scent glands.
b. Detects specific wavelengths of light and
transmits action potentials to the occipital lobe
via the optic nerve.
c. Produces different amplitude of action
potentials depending on intensity of a stimulus
*d. Contain stretch-induced ion channels that
lead to membrane depolarization when cells are
deformed.
88. We detect different auditory tones because
different sound frequencies
a. cause different action potential amplitudes in
auditory neurons
b. are processed by different auditory ganglia in
the ear lobe
c. travel at different speeds through the
vestibular fluids in the ear
*d. vibrate different parts of the cochlea, which
are detected by different mechanosensory cells.
89. We detect motion and position because
a. statoliths in our ears cause different action
potential frequencies in statitory neurons
*b. hair sensory cells detect movements of the
vestibular fluids in our ears
c. gravity pulls hairs on sensory cells downward
d. proprioceptors emit neurotransmitters in the
direction of gravity
e. ossicles vibrate different parts of the cochlea
in response to movement and gravity, which is
detected by different mechanosensors
90. Invertebrates use the following system to
detect gravity and maintain body orientation
*a. A sphere of sensory hair cells contains a
statolith that moves in response to gravity.
b. hair sensory cells detect movements of
vestibular fluids in the semicircular canals.
c. gravity pulls hairs on sensory cells downward
d. proprioceptors emit neurotransmitters in the
direction of gravity
e. ossicles vibrate different parts of the cochlea
in response to movement and gravity, which is
detected by different mechanosensors
91. Some plants respond to touch by
a. transmitting action potentials from cell to cell
via plasmodesmata
b. opening ion channels in specialized cells
c. Ions and water flow out of specialized cells,
resulting in cell flattening and leaf movement.
*d. All of the above.
92. Folding of Mimosa (sensitive plant) leaves
in response to touch
*a. is triggered by an action potential
b. is controlled by hormones
c. is controlled by neurotransmitters
d. is a stomatal response
93. In neural signaling, ionotropic receptors
*a. are ion channels that are opened (or closed)
in response to binding a neurotransmitter
b. are gap junctions that allow Na+ transport
across a synapse
c. are voltage-gated Ca++ channels that trigger
neurotransmitter uptake
d. are sensory neurons that detect
electromagnetic stimuli
e. direct chemotaxis of axons to guide neural
connections during development
94. In a resting neuron, the negative charge
inside the cell results from
a. Of the energy provided by ATP
b. Ion-selective channels allow diffusion of K+
c. The diffusion (concentration) gradient of K+
ions opposes the electrical gradient
d. The cell membrane is impermeable to Na+ or
Cl-ions.
e. 2 & 3
*f. All of the above
95. Sensory receptors
a. All connect to the same sensory center in the
brain
b. Interpret the quality of input stimuli
*c. Produce different frequency of action
potentials depending on intensity of a stimulus
d. Produce different amplitude of action
potentials depending on intensity of a stimulus
e. All of the above
96. The figure shows traces from action
potentials of normal neurons (control) and
neurons treated with alpha-dendrotoxin (αDTX). Dendrotoxin most likely affects
a. active transport
b. neurotransmitter release
c. Ca++ channel opening
d. Na+ channel opening
*e. K+ channel opening
Muscle/locomotion
97. Which of the following is true of the
arrangement of actin and myosin filaments
within a myofibril?
a. Thin filaments extend the entire way across
the sarcomere
b. Thick filaments are attached to the end walls
of the sarcomere
*c. Thin filaments are attached to the end walls
of the sarcomere
d. Thick filaments run towards the center from
each side of the sarcomere, leaving a gap in the
middle
e. Thin filaments traverse the sarcomere center
but do not reach the end walls
98. After ACh binds to the receptors in the
muscle fiber plasma membrane, Na+ floods into
the muscle fiber. Why?
a. Na+ signals for the muscle fiber to quit
binding to ACh
b. Na+ is a part of the ACh molecule that broke
off inside the cell
c. Na+ is so small that it is always diffusing
across the cell membrane
*d. Na+ depolarizes the cell membrane to
initiate an action potential
e. Na+ signals for ACh to be removed from the
synaptic cleft by the enzyme
acetylcholinesterase
99. Hydrostatic skeleton is one in which
a. A hard, exterior coating is used
b. A system of hard plates is used
*c. Fluid under pressure is used
d. Skeletal pieces are embedded in a gelatin-like
material
100. Each skeletal muscle cell constitutes a
single
a. motor unit
b. sarcolemma
c. myofibril
d. sarcomere
*e. muscle fiber
101. Which of the following is a common
neurotransmitter found invertebrate
neuromuscular junctions?
a. Serotonin
b. Glutamate
c. Dopamine
*d. Acetylcholine
e. Epinephrine
102. Which of the following is a common
neurotransmitter found in vertebrate
neuromuscular junctions?
*a. Acetylcholine
b. Serotonin
c. Glutamate
d. Dopamine
e. Epinephrine
103. Cross-bridges form between _____ and
_____ during muscular contraction.
*a. actin, myosin
b. actin, tropomyosin
c. myosin, troponin
d. myosin, tropomyosin
e. troponin, calmodulin
104. Neuromuscular junctions involve
a. a neural dendrite, a gap junction, and the
sarcoplasmic reticulum
b. a synapse, a myofibril, and troponin
*c. an axon terminal, acetylcholine, and ligand
gated ion channels
d. a synaptic cleft, norepinephrine, and an axon
terminal
e. an electrical synapse, a node of Ranvier, and
acetylcholine
105. An action potential in a muscle cell
*a. triggers Ca++ release from the sarcoplasmic
reticulum
b. is propagated through voltage gated Ca++
channels
c. is initiated by myosin binding to actin
filaments
d. causes release of acetylcholine
e. all of the above
106. What would happen to a myofibril if ATP
were depleted from a muscle cell?
*a. Myosin could not release from actin
b. Myosin could not bind actin
c. Myosin could not perform a power stroke
d. Actin would depolymerize
e. Myosin could not hydrolyze
107. When during a muscle contraction
sequence is ATP hydrolyzed to provide power?
a. cross bridge formation (binding)
b. power stroke
c. Detachment of myosin from actin
*d. Reactivation of myosin heads
e. to remove tropomyosin from the binding sites
on actin
108. Calcium in skeletal muscle cells
a. Creates an action potential
b. Binds myosin
c. Binds actin
*d. Regulates availability of myosin binding
sites on actin
e. Is stored in the symplastic infundibulum
Reproduction
109. A pollen grain
a. is a diploid organism
b. is a female gametophyte
c. contains an egg cell
*d. produces 2 sperm cells
e. None of the above
110. In plant reproduction, alternation of
generations refers to alternating between
a. male and female
b. embryo and endosperm
*c. haploid and diploid
d. epiphyte and halophyte
e. monocot and dicot
111. In mammals, male sex characteristics are
determined by all the following EXCEPT
a. Having a Y chromosome
*b. Having only one X chromosome
c. Testes determining factor
d. Testosterone levels
112. Which of the following is NOT true for
both male and female mammalian
gametogenesis?
*a. One primary cell produces four mature
gametes.
b. Germ line cells multiply by mitosis.
c. Primary cells (spermatocytes and oocytes) are
diploid.
d. Gametes are formed by meiosis.
e. Gametes develop in the gonads.
113. In mammalian females, germ cells
(oocytes) are
a. not produced until puberty.
*b. nearly all produced in the fetus.
c. fully mature gametes at birth.
d. produced in the embryo sac.
e. arrested in mitosis until puberty.
114. Which of the following is NOT TRUE of
the placenta
a. It functions in exchange of gases, nutrients
and wastes between mother and fetus
b. It develops from maternal and fetal tissue
c. The fetal portion (chorion) has chorionic villi
providing a large surface area for exchange
*d. Blood of the mother and fetus mix
e. It transports drugs and alcohol from mother to
fetus
115. In mammals, the primary signal of a
successful fertilization is
*a. the uterus produces chorionic gonadotropin
which signals the corpus luteum in the ovary
b. the follicle produces estrogen, which signals
the corpus luteum to decrease progesterone
c. the corpus luteum in the ovary produces
estrodiol, which signals implantation in the
uterus
d. the completion of meiosis II triggers estrogen
and progesterone, which signal the uterus
e. mechanosensors in the uterine wall are are
depolarized by implantation, triggering an action
potential
115. Females produce eggs. Which of the
following is NOT a feature of meiosis in most
female germlines?
a. Chromosome number is reduced from 4 to 1.
b. Unequal cytokinesis results in a single larger
cell with most of the cytoplasm.
*c. The diploid oocyte is the final product.
d. Polar bodies contribute to reduction of
chromosome number.
e. None. All of the above statements are true.
116. Which of the following is NOT a form of
asexual reproduction?
a. Mitosis
b. Budding
*c. Gender switching in fish
d. Regeneration
e. Parthenogenesis
117. Which of the following is NOT an
advantage of asexual reproduction?
a. Able to reproduce even if isolated
b. Able to reproduce rapidly
c. Can generate large numbers of offspring
*d. Greater genetic variation
e. All of the above
f. None of the above
118. The table above is derived from the
Komodo dragon parthenogenesis article. What
aspects of this data set support the hypothesis
that Sungai’s offspring are the result of sexual
reproduction?
a. All of the offspring are homozygous at each
of the microsatellite loci analyzed.
b. The absence of the 133 microsatellite marker
in the offspring at the K06 locus.
c. All of the microsatellite markers of the
offspring are found in Sungai’s DNA.
*d. None. All of the above statements support
the hypothesis that Sungai’s offspring are the
result of parthenogenesis.
119. Sex determination in Komodo dragons is
based on a system where females are WZ
(dissimilar chromosomes) and males are ZZ
(similar chromosomes). Based on the
observations about parthenogenesis in Komodo
dragons, what sex were the offspring produced
by parthenogenesis?
a. Female
*b. Male
c. The offspring could be either male or female.
d. The offspring would be of indeterminate sex.
c. The enhancers fail to activate the expression
of either Igf2 or H19.
122. Based on what we discussed about
mammalian imprinting, which of the following
is a characteristic of epigenetic gene regulation?
a. Epigenetic DNA methylation
b. is the same between homologous chromosomes
in early mammalian embryos.
b. Epigenetic imprinting results in the removal
of genes from the chromosomes.
*c. Epigenetic DNA methylation can result in
genes not being transcribed.
123. Which of the following is a characteristic of
sexual reproduction?
*a. The embryo is usually the result of the fusion
of gametes from different genetic backgrounds.
b. The embryo is usually the result of the fusion
of diploid gametes from two different parents.
c. The species is less able to adapt to changes in
the environment due to less genetic diversity
within the population.
d. The genome is less likely to retain deleterious
mutations in critical genes.
120. The figure above is from the “Mice without
a Father” article. Based on what is shown above
and what we discussed in class, which of the
following is NOT
true?
*a. Epigenetics does not affect gene expression.
b. The maternally contributed genes are
necessary for normal development of the
embryo.
c. Gene expression from the paternal genome is
necessary for extraembryonic tissue
development.
121.The figure above is from the “Mice without
a Father” article. The differentially methylated
domain (DMD-Illustrated by the green bar if
it is methylated (CH3).) is key to this
epigenetic gene regulation. Which of the
following is the result if this region is NOT
methylated (A nonmethlyated DMD is
illustrated by the presence of the blue bar.)?
a. The enhancers activate the expression of Igf2.
*b. The enhancers activate the expression of
H19.
124. Recombination occurs…
a. as gametes are in the final stages of
maturation.
b. during the separation of homologous
chromosomes in mitosis.
*c. during the separation of homologous
chromosomes in meiosis I.
d. as the sister chromatids separate during
mitosis.
125. of the following is NOT a mechanism for
sex determination?
a. Temperature
b. The X chromosome to autosomal
chromosome ratio.
c. Sex determining factors on sex chromosomes.
*d. None. All of the above are mechanisms for
sex determination.
126. Which of the following is a characteristic of
asexual reproduction?
a. It is limited to invertebrates.
b. It allows for the maintenance of greater
genetic diversity.
*c. It allows for the maintenance of successful
genotypes.
d. It requires meiotic cell division.
b. sharks
*c. mammals
d. bees
127. In plants, …..
a. 1n individuals produce gametes via meiosis.
b. 2n individuals produce gametes via mitosis.
*c. 1n individuals produce gametes via mitosis.
d. 2n individuals produce gametes via meiosis.
128. Which of the following is a characteristic of
pollen and stigma self-incompatibility?
a. It prevents the pollen and stigma from
adhering to each other.
b. It allows plants to self fertilize
*c. It inhibits pollen tube growth.
d. It reduces genetic diversity.
129. Double fertilization in flowering plants…
*a. results in the formation of a 3n endosperm.
b. allows for plants to self fertilize.
c. is a form of parthenogenesis.
d. is a system that improves fertility since only
one of the sperm needs to successfully fertilize
the egg.
130. In the alternation of generations in
flowering plant lifecycles,
a. the haploid phase is often free living.
*b. the diploid phase is dominant.
c. the diploid phase produces the gametes.
d. the endosperm is haploid.
131. Based on the feature investigation about
plant in vitro fertilization, which of the
following statements is NOT true about plant in
vitro fertilization?
a. In vitro fertilization was not reported until
1993 because of the difficulty of isolating sperm
and egg cells in plants.
*b. In vitro pollination and in vitro fertilization
are equivalent.
c. The successful fertilization was demonstrated
by the expression of paternal- and maternalderived markers.
d. The fusion of egg and sperm cells was
achieved by electric shock.
132. Parthenogenic offspring have been noted in
all of the following except:
a. lizards
133. The figure above is from the “Mice without
a Father” article. Based on what is shown above
and what we discussed in class, which of the
following is NOT true?
*a. The expression of paternal genes is not
required for normal development.
b. The maternally contributed genes are
necessary for normal development of the
embryo.
c. Gene expression from the paternal genome is
necessary for extraembryonic tissue
development.
134. Which of the following outcomes would
result if parthenogenesis were the result of either
failure of cytokinesis in meiosis II or fusion of
the oocyte and the second polar body?
a. XX and XX
b. XX
c. XX
*d. XX and XX
e. XX f. XX
Disease
135. Which of the following is the best
definition of disease?
a. Any condition that leads to cell death.
b. Any condition caused by infection with
pathogens, such as bacteria or viruses.
c. Any condition caused by genetic mutations or
inheritance of defective genes.
*d. Any condition that impairs normal function.
e. None of the above.
136. Which of the following is NOT a
characteristic of cancer
a. Cancer cells divide uncontrollably.
b. Cancer is a malignant disease, meaning that it
progressively becomes worse.
*c. Cancer is caused by one single mutation that
results in increased cell division.
d. Cancer is relatively rare at the cellular level,
but common among organisms.
e. Cancer can metastasize, spreading to other
tissues.
137. Activated p53 halts the cell cycle and
promotes DNA repair, while inactivated p53 is
quickly broken down. p53 is activated in the
presence of DNA damage. In the scenario
depicted, the p53 gene is mutated and therefore
the p53 protein can never be activated. Will this
cell divide?
a. Yes, because the mutated p53 will induce the
expression of genes that promote cell division.
*b. Yes, because the mutated p53 cannot induce
expression of genes that halt the cell cycle.
c. No, because the mutated p53 will inhibit
proteins that promote cell division.
d. No, because the mutated p53 will be detected
by the cell, and the cell will not survive.
138. Radiation therapy for cancer induces severe
DNA damage. Which of the following cancer
cells is this therapy LEAST likely to work on?
a. Cancer cells that already have many
mutations.
b. Cancer cells that have gain-of-function
mutations in a growth factor receptor, such that
the receptor is always activated.
*c. Cancer cells that have loss-of-function
mutations in p53, such that p53 cannot be
activated.
d. Cancer cells that still retain “self” signals and
can evade the immune system.
139. Consider a genetic mutation in a gene for a
death signal receptor, “Y”. In this mutation, a
stop codon has been inserted in the middle of the
coding region of the gene. What is the most
likely outcome?
*a. Only part of protein “Y” will be translated,
and the resulting protein will probably not be
functional.
b. RNA polymerase will detect the mutation and
the gene will not be transcribed.
c. The ribosomes will detect the mutation in the
mRNA and translation will not occur.
d. The ribosomes will recognize the base pair
mismatch in the mRNA and correct the
mutation.
140. What is genomic instability?
a. A mutation in a gene for a protein that detects
DNA damage.
b. Any mutation that deletes or copies a large
chunk of a chromosome.
c. When chromosomes break up into many
smaller chromosomes.
*d. The rapid accumulation of mutations over
time.
141. Which of the following cellular processes
in cancer cells do NOT directly promote
metastasis?
a. Migration
b. Maintaining survival signals
c. Cell division
*d. Apoptosis
142. Consider a gene encoding for a protein
important for growth factor signaling. When
mutated, this protein becomes constantly active.
This gene is most likely a:
a. Tumor suppressor
b. Tumor promoter
*c. Proto-oncogene
d. Carcinogen
143. Imagine a mutated form of the epidermal
growth factor (EGF) receptor. This receptor now
signals even when there is no EGF bound to it.
What is the result?
*a. The signal cascade will always be active, so
the cell will always behave as if it is receiving
growth signals and will divide.
b. Since the cell cannot bind to EGF, it cannot
receive growth signals and will not divide.
c. The signal transduction cascade will always
be active, but because there is no EGF the cell
will not divide.
d. The cell will die because the signal
transduction cascade produces toxic byproducts.
144. Which of the following is most likely to be
tumor suppressor?
a. a gene that increases cell proliferation.
b. a gene which codes a fluorescent protein.
*c. a gene important for repairing DNA damage.
d. a gene that enables adaptation to hypoxia (low
oxygen).
e. a gene that stimulates angiogenesis (formation
of new blood vessels).
145. The acquired immune system is very
effective. Why?
*a. The cells of the acquired immune system
recognize very specific antigens, so only
particular pathogens or abnormal cells are
targeted.
b. The cells of the acquired immune system can
recognize very general “non-self” signals, so
each cell can target a wide variety of pathogens.
c. The acquired immune system can mount an
effective response within a few hours of
infection.
146. What function does the innate immune
system serve?
a. The innate immune system takes time to ramp
up in response to a specific antigen.
b. Innate immune cells are important early in an
infection, but after antibodies are produced they
no longer contribute to eliminating the
pathogens.
*c. Innate immune cells recognize general “nonself” signals, so they can target pathogens or
abnormal cells very early and quickly.
d. All of the above.
147. What does “immunological memory”
mean?
a. The cells of the immune system store antigens
from previous infections.
*b. Acquired immune cells such as B and T cells
are primed during the first infection. During the
second infection, these cells can respond much
more quickly.
c. Once antibodies are generated, they never
ever break down.
148. The function of B cells is to:
*a. Produce antibodies, which bind to antigens.
b. Activate cytotoxic T cells, which kill
abnormal or infected cells.
c. Attack antigen-bearing bodies marked with
antibodies.
d. Help T cells by providing growth signals.
149. Why is it so difficult to design a vaccine
against HIV?
a. HIV mutates very rapidly, so the antigens
constantly change.
b. HIV infects and kills cells that normally help
fight off viral infections.
c. HIV integrates its genome into the host
genome, so the viral DNA can hide from the
immune system inside host cells.
*d. All of the above.
150. The prion protein is transcribed from the
________ gene.
a. PRIA
*b. PRNP
c. PPSC
d. PRIO
151. Which of the following best describes the
cause of prion diseases?
a. The body is infected with the prion virus,
which attacks the brain and lymph nodes of the
animal.
b. The body is infected with a bacterium,
Clostridium prionii, when ingesting
contaminated food, which then moves up the
nervous system to the brain.
c. The immune system attacks the body’s own
tissues, reacting with the prion protein to cause
inflammation in the brain.
*d. The normal version of the prion protein in
the body misfolds into a harmful conformation.
152. Prion diseases are often referred to as
spongiform encephalopathies. What does the
term spongiform refer to?
a. The organs of the animal’s body absorb
excess water, like a sponge, and swell slightly.
*b. The brain of the animal develops holes in it,
so that it looks like Swiss cheese under the
microscope.
c. The heart of the animal develops holes in it,
so that it looks like Swiss cheese under the
microscope.
d. The skin of the animal becomes soft and
spongy to the touch.
153. Which of the following diseases is found
in deer and elk and has spread from Colorado
and the Western United States to other parts of
the U.S. and Canada?
a. TME (Transmissible mink encephalopathy)
b. BSE (Bovine spongiform encephalopathy)
*c. CWD (Chronic Wasting Disease)
d. CJD (Creutzfeldt-Jakob Disease)
154. Which of the following prion diseases is
found in a human, as opposed to a non-human
mammalian host?
*a. CJD (Creutzfeldt-Jakob Disease)
b. CWD (Chronic Wasting Disease)
c. TME (Transmissible Mink Encephalopathy)
d. Scrapie
155. In class, we discussed Koch’s postulates as
a methodology for scientists to confirm the
cause of prion diseases (in other words, how can
we confirm that prions cause the disease of
scrapie?) Which of the following statements is
NOT part of this process?
a. We can detect (misfolded) prions in all cases
of diseased sheep (sheep that are sick with
scrapie).
b. If we infect sheep with prions from another
infected sheep, the sheep will become sick.
*c. If we infect humans with prions from an
infected sheep, the humans will become sick.
d. We can identify the presence of prions in the
new (experimentally infected) host.
156. Which of the following statements is
incorrect?
a. Infectious prions can spread to other
organisms by the environment or by
experimental inoculation.
b. The normal prion protein is not harmful in the
brain and has some functions, like binding
copper.
c. Prion diseases cause severe neurological
issues and are inevitably fatal.
*d. All of the prion diseases we studied in class
are commonly found in humans.
157. What is the “protein hypothesis” in the
context of prion diseases?
a. Ingestion of a diet high in protein content has
been recently proven to provide a therapy for
those infected with prion diseases.
*b. Prion diseases involve a misfolded version
of protein in your body.
c. The bacterium responsible for prion disease is
highly fatal because of a toxic protein produced
and secreted through the cell wall and cell
membrane.
d. Prion diseases are associated with the
cleavage of an important protein in the gut of the
animal into three toxic pieces, leading to illness,
neurological changes, and eventually death.
158. Which of the following does NOT
correctly describe a common feature of prion
diseases, including the diseases we researched
for class?
a. They are associated with cognitive,
behavioral, and other neurological signs and
symptoms.
b. They are associated with the same genetic
locus in each case.
c. They are associated with changes in the
central nervous system.
*d. They are found in humans, mammals, and
cold-blooded species such as fish and
amphibians.
159. Scientists at the National Animal Disease
Center…(complete the sentence)
a. Work in teams composed of people with
different specialties.
b. Are part of the largest federally funded
veterinary research facility.
c. Must be very careful and safety conscious as
they work with potentially deadly pathogens.
*d. All of the above