Final Exam BIOL 546/ 310+ Qs & Ans/ 2024-
2025.
if an AP was initiated at the center of the axon, what direction would it travel -
Answer: both direction
If a neuron were experimentally stimulated at both ends simultaneously - Answer:
the Ads would stop as they meet in the middle
what is the neurological effect of a chemical such as sarin, the inhibits AChE in the
neuromuscular synapse - Answer: nerve continues to send impulse to the muscles
(seizures)
what determines if a synapse is excitatory or inhibitory - Answer: type of NT and
type of ion channel opened by the postsynaptic receptor activated by NT
the vertebrate neural system conducts signals in only one direction. This one way
signaling occurs - Answer: as a result of voltage gated Na Channels, bc the
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,postsynaptic ending cannot release NT, bv only the postsynaptic membrane can
bind NT
All of the following are true statements about the action potential EXCEPT:
a) Opening of the voltage-gated Na-channels will move the membrane potential
to the equilibrium potential of Na.
b) Opening of voltage-gated K-channels will move the membrane potential to the
equilibrium potential of K.
c) The Hodgkin cycle causes the fast change in membrane potential during the
rising phase of the action potential.
d) The falling phase of the AP is mainly due to the movement of K+ ions.
e) Voltage-gated Na-channels stay open longer than voltage-gated K-channels. -
Answer: e) Voltage-gated Na-channels stay open longer than voltage-gated K-
channels.
Scientists discovered a new animal species with nerve cells physiologically similar
to nerve cells found in other animals. The membrane potential when only sodium
ions can move across the membrane was measured at +116 mV. What is the
sodium concentration outside the nerve cell if the sodium concentration inside
the cell is 1 mM?
a) 1 M
b) 0.232 M
c) 0.116 M
d) 0.58 M
e) 0.1 M - Answer: e) 0.1 M
3. Which neurotransmitter binds to the nicotinic ACh receptor?
a) muscarine
b) atopine
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,c) norepinephrine
d) glutamate
e) None of the above - Answer: e) None of the above ***
4. The period of excitability of neuron during which both Na+ and K+ activation
can occur is called the
a) interphase period.
b) relative refractory period.
c) absolute refractory period.
d) hyperexcitable period.
e) latent period - Answer: b) relative refractory period. ***
Excitation of the cone cell by blue light results in the production of an action
potential in the connected bipolar cell.
a) true
b) false - Answer: F
6. Which concept is the defining feature of the discipline of physiology?
a) Descent with modification
b) Homeostasis
c) Evolution
d) Equilibrium
e) Differentiation - Answer: homeostasis
7. Stimulation of a hair cell results in changes in the hair cell membrane such as
a) opening of voltage-gated Na+ channels.
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, b) opening of voltage-gated K+ channels.
c) answers a and b.
d) none of the above. - Answer: d) none of the above. ***
8. What is the general purpose of positive feedback mechanisms?
a) To maintain a constant internal environment
b) To anticipate changes in the environment
c) To return a variable toward the set point
d) To bring about a rapid change in the body
e) To detect changes in the external environment - Answer: d) To bring about a
rapid change in the body
9. You are designing a drug. You'd like to deliver the drug by creating a skin patch
that is impregnated with the drug and allowing the drug to diffuse through the
layers of the skin to reach the underlying tissues and bloodstream. Which of these
chemical changes might you make to increase the number of drug molecules that
diffuse through the layers of skin cells?
a) Increasing the number of nitrogen atoms in the drug
b) Decreasing the number of nonpolar groups in the drug
c) Decreasing the number of polar groups in the drug
d) Increasing the number of oxygen atoms in the drug - Answer: c) Decreasing the
number of polar groups in the drug ***
10. What comes last in the release of neurotransmitters from synaptic vesicles?
a) fusion.
b) priming.
c) docking
d) opening of Ca channels - Answer: fusion
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2025.
if an AP was initiated at the center of the axon, what direction would it travel -
Answer: both direction
If a neuron were experimentally stimulated at both ends simultaneously - Answer:
the Ads would stop as they meet in the middle
what is the neurological effect of a chemical such as sarin, the inhibits AChE in the
neuromuscular synapse - Answer: nerve continues to send impulse to the muscles
(seizures)
what determines if a synapse is excitatory or inhibitory - Answer: type of NT and
type of ion channel opened by the postsynaptic receptor activated by NT
the vertebrate neural system conducts signals in only one direction. This one way
signaling occurs - Answer: as a result of voltage gated Na Channels, bc the
Page 1 of 100
,postsynaptic ending cannot release NT, bv only the postsynaptic membrane can
bind NT
All of the following are true statements about the action potential EXCEPT:
a) Opening of the voltage-gated Na-channels will move the membrane potential
to the equilibrium potential of Na.
b) Opening of voltage-gated K-channels will move the membrane potential to the
equilibrium potential of K.
c) The Hodgkin cycle causes the fast change in membrane potential during the
rising phase of the action potential.
d) The falling phase of the AP is mainly due to the movement of K+ ions.
e) Voltage-gated Na-channels stay open longer than voltage-gated K-channels. -
Answer: e) Voltage-gated Na-channels stay open longer than voltage-gated K-
channels.
Scientists discovered a new animal species with nerve cells physiologically similar
to nerve cells found in other animals. The membrane potential when only sodium
ions can move across the membrane was measured at +116 mV. What is the
sodium concentration outside the nerve cell if the sodium concentration inside
the cell is 1 mM?
a) 1 M
b) 0.232 M
c) 0.116 M
d) 0.58 M
e) 0.1 M - Answer: e) 0.1 M
3. Which neurotransmitter binds to the nicotinic ACh receptor?
a) muscarine
b) atopine
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,c) norepinephrine
d) glutamate
e) None of the above - Answer: e) None of the above ***
4. The period of excitability of neuron during which both Na+ and K+ activation
can occur is called the
a) interphase period.
b) relative refractory period.
c) absolute refractory period.
d) hyperexcitable period.
e) latent period - Answer: b) relative refractory period. ***
Excitation of the cone cell by blue light results in the production of an action
potential in the connected bipolar cell.
a) true
b) false - Answer: F
6. Which concept is the defining feature of the discipline of physiology?
a) Descent with modification
b) Homeostasis
c) Evolution
d) Equilibrium
e) Differentiation - Answer: homeostasis
7. Stimulation of a hair cell results in changes in the hair cell membrane such as
a) opening of voltage-gated Na+ channels.
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, b) opening of voltage-gated K+ channels.
c) answers a and b.
d) none of the above. - Answer: d) none of the above. ***
8. What is the general purpose of positive feedback mechanisms?
a) To maintain a constant internal environment
b) To anticipate changes in the environment
c) To return a variable toward the set point
d) To bring about a rapid change in the body
e) To detect changes in the external environment - Answer: d) To bring about a
rapid change in the body
9. You are designing a drug. You'd like to deliver the drug by creating a skin patch
that is impregnated with the drug and allowing the drug to diffuse through the
layers of the skin to reach the underlying tissues and bloodstream. Which of these
chemical changes might you make to increase the number of drug molecules that
diffuse through the layers of skin cells?
a) Increasing the number of nitrogen atoms in the drug
b) Decreasing the number of nonpolar groups in the drug
c) Decreasing the number of polar groups in the drug
d) Increasing the number of oxygen atoms in the drug - Answer: c) Decreasing the
number of polar groups in the drug ***
10. What comes last in the release of neurotransmitters from synaptic vesicles?
a) fusion.
b) priming.
c) docking
d) opening of Ca channels - Answer: fusion
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