BIO SCI E109 Test Answers Questions and Answers
Question 1.
Select which statement(s) are NOT TRUE of action potentials.
Correct Answer: The inactivation gate reduces permeability in the voltage-gated
K+ channel. Repolarization is driven by K+ permeability. Voltage-gated channels
for Na+ and K+ have the same threshold Vm. Depolarization would not happen if
not for voltage-gated Na+ channels.
Question 2.
Where is the blood when the linear flow speed reaches its minimum? exiting the left
ventricle in the systemic veins capillary beds linear flow speed is the same everywhere
(Law of Continuity)
Correct Answer: capillary beds
Question 3.
What does line viii represent? The equilibrium potential for Ca2+. The equilibrium potential
for Na+. The resting membrane potential. The threshold potential. The equilibrium
potential for K+.
Correct Answer: The inactivation gate reduces permeability in the voltage-gated
K+ channel.
Question 4.
The below graphs show the membrane potential of individual synapses on a dendrite (red
and blue curves), as well as the overall membrane potential of the cell body (black, dashed
curve). Choose the graph(s) that illustrate temporal and/or spatial summation in a neuron.
Correct Answer: --
Question 5.
Is the distance between a chemical synapse and the axon hillock important for whether an
action potential is generated? Yes, because the electromotive force decreases with
distance. No, distance does not matter because temporal summation is more important for
the generation of action potentials. No, distance is not important because electricity
moves so rapidly. Yes, changes in Vm in the dendrites depend on diffusion, which varies
with distance.
Correct Answer: Yes, changes in Vm in the dendrites depend on diffusion, which
varies with distance.
Question 6.
Match the following characteristics to either polysynaptic, monosynaptic reflexes or both.
Multiple synapses in parallel. Multiple neurons. Multiple synapses in series.
Correct Answer: Multiple synapses in parallel. - Both Multiple neurons. - Both
Multiple synapses in series. - Polysynaptic
Question 7.
Select the correct order of responses your body will exhibit if visiting Joshua Tree National
Park when the temperature is 38C (100F).
Correct Answer: 1. cutaneous thermoreceptors are excited 2. signal travels
through ascending tract of spinal cord 3. hypothalamus integrates sensory info
4. efferent pathway stimulates sympathetic nervous system 5. vasodilation of
blood vessels Sensory receptors recognize condition(s) first and become
, activated, which send an action potential into the spinal cord which then
'ascends' along the ascending tract to the brain where the hypothalamus
integrates the sensory information and if it determines the current state is too
far from the set point it sends out an efferent signal to the prompt some
change, in this case it is vasodilation of blood vessels which allow you to
dissipate heat by bringing blood to the surface of your skin.
Question 8.
At beginning of repolarization, what is the most likely state of a Na+ channel?
Correct Answer: The activation gate is open and the inactivation gate is closed It
is most-likely that the inactivation gate is closed because the membrane at this
time is repolarizing.
Question 9.
What events are likely to occur in response to action by a parasympathetic pathway?
Gastric (i.e. digestive) motility increases. Insulin secretion decreases. Contractility in the
heart increases.
Correct Answer: Gastric (i.e. digestive) motility increases.
Question 10.
Which of the following statements are TRUE about neurons?
Correct Answer: Graded potentials occur within an axon inside of a myelinating
schwann cell. The dendrites can integrate stimuli from inhibitory and excitatory
synapses.The axon hillock serves as the spike-initiating zone because of the
presence of voltage-gated channels.
Question 11.
Why does a second stimulus early in the relative refractory period have to be stronger to
initiate an action potential? Because the membrane is hyperpolarized Because the
threshold voltage is greater Because the membrane is permeable to Cl-
Correct Answer: Because the membrane is hyperpolarized Because the
threshold voltage is greater
Question 12.
Which of the following statements are FALSE? Muscles are one type of connective tissue.
Ground substance may be liquid. Connective tissues possess cells. Adipose tissue has a
crystalized matrix.
Correct Answer: Muscles are one type of connective tissue. Muscles are their
own type of tissue.
Question 13.
What does homeostasis in body temperature suggest? That your physiology tries to
maintain body temperature against perturbations from activity. That body temperature
never remains consistent. That your body temperature never changes.
Correct Answer: That your physiology tries to maintain body temperature
against perturbations from activity.
Question 14.
Which of the following efferent pathways are ONLY involuntary? Sympathetic Sensory
Automatic Parasympathetic
Correct Answer: Parasympathetic Sympathetic
Question 1.
Select which statement(s) are NOT TRUE of action potentials.
Correct Answer: The inactivation gate reduces permeability in the voltage-gated
K+ channel. Repolarization is driven by K+ permeability. Voltage-gated channels
for Na+ and K+ have the same threshold Vm. Depolarization would not happen if
not for voltage-gated Na+ channels.
Question 2.
Where is the blood when the linear flow speed reaches its minimum? exiting the left
ventricle in the systemic veins capillary beds linear flow speed is the same everywhere
(Law of Continuity)
Correct Answer: capillary beds
Question 3.
What does line viii represent? The equilibrium potential for Ca2+. The equilibrium potential
for Na+. The resting membrane potential. The threshold potential. The equilibrium
potential for K+.
Correct Answer: The inactivation gate reduces permeability in the voltage-gated
K+ channel.
Question 4.
The below graphs show the membrane potential of individual synapses on a dendrite (red
and blue curves), as well as the overall membrane potential of the cell body (black, dashed
curve). Choose the graph(s) that illustrate temporal and/or spatial summation in a neuron.
Correct Answer: --
Question 5.
Is the distance between a chemical synapse and the axon hillock important for whether an
action potential is generated? Yes, because the electromotive force decreases with
distance. No, distance does not matter because temporal summation is more important for
the generation of action potentials. No, distance is not important because electricity
moves so rapidly. Yes, changes in Vm in the dendrites depend on diffusion, which varies
with distance.
Correct Answer: Yes, changes in Vm in the dendrites depend on diffusion, which
varies with distance.
Question 6.
Match the following characteristics to either polysynaptic, monosynaptic reflexes or both.
Multiple synapses in parallel. Multiple neurons. Multiple synapses in series.
Correct Answer: Multiple synapses in parallel. - Both Multiple neurons. - Both
Multiple synapses in series. - Polysynaptic
Question 7.
Select the correct order of responses your body will exhibit if visiting Joshua Tree National
Park when the temperature is 38C (100F).
Correct Answer: 1. cutaneous thermoreceptors are excited 2. signal travels
through ascending tract of spinal cord 3. hypothalamus integrates sensory info
4. efferent pathway stimulates sympathetic nervous system 5. vasodilation of
blood vessels Sensory receptors recognize condition(s) first and become
, activated, which send an action potential into the spinal cord which then
'ascends' along the ascending tract to the brain where the hypothalamus
integrates the sensory information and if it determines the current state is too
far from the set point it sends out an efferent signal to the prompt some
change, in this case it is vasodilation of blood vessels which allow you to
dissipate heat by bringing blood to the surface of your skin.
Question 8.
At beginning of repolarization, what is the most likely state of a Na+ channel?
Correct Answer: The activation gate is open and the inactivation gate is closed It
is most-likely that the inactivation gate is closed because the membrane at this
time is repolarizing.
Question 9.
What events are likely to occur in response to action by a parasympathetic pathway?
Gastric (i.e. digestive) motility increases. Insulin secretion decreases. Contractility in the
heart increases.
Correct Answer: Gastric (i.e. digestive) motility increases.
Question 10.
Which of the following statements are TRUE about neurons?
Correct Answer: Graded potentials occur within an axon inside of a myelinating
schwann cell. The dendrites can integrate stimuli from inhibitory and excitatory
synapses.The axon hillock serves as the spike-initiating zone because of the
presence of voltage-gated channels.
Question 11.
Why does a second stimulus early in the relative refractory period have to be stronger to
initiate an action potential? Because the membrane is hyperpolarized Because the
threshold voltage is greater Because the membrane is permeable to Cl-
Correct Answer: Because the membrane is hyperpolarized Because the
threshold voltage is greater
Question 12.
Which of the following statements are FALSE? Muscles are one type of connective tissue.
Ground substance may be liquid. Connective tissues possess cells. Adipose tissue has a
crystalized matrix.
Correct Answer: Muscles are one type of connective tissue. Muscles are their
own type of tissue.
Question 13.
What does homeostasis in body temperature suggest? That your physiology tries to
maintain body temperature against perturbations from activity. That body temperature
never remains consistent. That your body temperature never changes.
Correct Answer: That your physiology tries to maintain body temperature
against perturbations from activity.
Question 14.
Which of the following efferent pathways are ONLY involuntary? Sympathetic Sensory
Automatic Parasympathetic
Correct Answer: Parasympathetic Sympathetic
