ESSENTIALS OF CELL BIOLOGY AND
NEUROSCIENCE EXAM #1 QUESTIONS
WITH COMPLETE SOLUTIONS
What effect would cutting the ventral roots in the spinal cord have?
a) cutting the ventral roots would affect only sensory information going into the brain
b) cutting the ventral roots would affect only muscle contractions
c) cutting the ventral roots would affect both sensory information going to the brain and
the ability of motor neurons to make the muscles contract
d) a, b and c are all correct
e) none of the above - ANSWER-b) cutting the ventral roots would affect only muscle
contractions
Corpus callosum is located in the _______
a) hindbrain
b) forebrain
c) midbrain
d) cerebellum - ANSWER-c) midbrain
The human cerebrum can be divided up into four lobes. These are the ______, ______,
______, and ________lobes.
a) dorsal, ventral, rostral and caudal
b) cerebrum, brain stem, spinal cord and cerebellum
c) forebrain, midbrain, hindbrain, and cerebellum
d) occipital, temporal, frontal and parietal - ANSWER-d) occipital, temporal, frontal and
parietal
Pick the correct statement(s) concerning active membrane transport:
a) it occurs against the concentration gradient
b) it requires energy
c) it occurs down the concentration gradient
d) a & b are both correct
e) b & c are both correct - ANSWER-d) a & b are both correct
Ion channels _________________
a) only allow ions to move down their concentration gradients
b) only allow ions to move against their concentration gradients
c) alway require addition of energy in some form to move ions
d) a & c are correct - ANSWER-a) only allow ions to move down their concentration
gradients
The most important function for K+ leak channels is to:
a) generate and maintain the resting potential
, b) generate the rising phase of the action potential
c) transport sodium ions out of the cell following the action potential
d) generate EPSPs when neurotransmitter is released from the presynaptic terminal
e) provide enough depolarization in the neuron to reach threshold for firing an action
potential - ANSWER-a) generate and maintain the resting membrane potential
A protein located in the membrane of nerve cells moves glucose into the cell at the
same time as sodium ions are flowing down their concentration gradient. This would be
an example of which type of membrane protein?
a) symporter
b) antiporter
c) ion channel
d) passive diffusion - ANSWER-a) symporter
What would the voltage be across a phospholipid bilayer membrane that is permeable
only to sodium ions be if the concentration of sodium on one side of the membrane
(outside) is 100mM, and on the other side (inside) is 10mM? Assume that the system is
at equilibrium and at body temperature.
log100= 2, log 10=1, log1=0, log0.1=-1, log0.01=-2
a) +31 mV
b)+62 mV
c)-31 mV
d) -62mV - ANSWER-b) +62mV
What happens to resting membrane potential if the extracellular potassium
concentration increases from the usual 5mM to a higher concentration?
a) Nothing, the resting membrane potential would not change, only the equilibrium
potential for potassium would change
b) it would become less negative
c) it would become more negative
d) it would become 0mV - ANSWER-b) It would become less negative
Consider a neuron in which the intracellular fluid has a potassium concentration of
100mM, and the extracellular fluid has a potassium concentration of 1mM. If the cell
membrane is permeable only to potassium ions, what is the voltage across the
membrane? [assume that the system is at equilibrium and at body temperature; log
100=2, log 10=1 , log 1=0 , log0.1 = -1 , log 0.01 = -2]
a) -124 mV
b) +124 mV
c) -62 mV
d) +62 mV
e) 0 mV - ANSWER-a) -124 mV
When a neuron is at rest _________
a) the membrane permeability for potassium is higher than the membrane permeability
for sodium
NEUROSCIENCE EXAM #1 QUESTIONS
WITH COMPLETE SOLUTIONS
What effect would cutting the ventral roots in the spinal cord have?
a) cutting the ventral roots would affect only sensory information going into the brain
b) cutting the ventral roots would affect only muscle contractions
c) cutting the ventral roots would affect both sensory information going to the brain and
the ability of motor neurons to make the muscles contract
d) a, b and c are all correct
e) none of the above - ANSWER-b) cutting the ventral roots would affect only muscle
contractions
Corpus callosum is located in the _______
a) hindbrain
b) forebrain
c) midbrain
d) cerebellum - ANSWER-c) midbrain
The human cerebrum can be divided up into four lobes. These are the ______, ______,
______, and ________lobes.
a) dorsal, ventral, rostral and caudal
b) cerebrum, brain stem, spinal cord and cerebellum
c) forebrain, midbrain, hindbrain, and cerebellum
d) occipital, temporal, frontal and parietal - ANSWER-d) occipital, temporal, frontal and
parietal
Pick the correct statement(s) concerning active membrane transport:
a) it occurs against the concentration gradient
b) it requires energy
c) it occurs down the concentration gradient
d) a & b are both correct
e) b & c are both correct - ANSWER-d) a & b are both correct
Ion channels _________________
a) only allow ions to move down their concentration gradients
b) only allow ions to move against their concentration gradients
c) alway require addition of energy in some form to move ions
d) a & c are correct - ANSWER-a) only allow ions to move down their concentration
gradients
The most important function for K+ leak channels is to:
a) generate and maintain the resting potential
, b) generate the rising phase of the action potential
c) transport sodium ions out of the cell following the action potential
d) generate EPSPs when neurotransmitter is released from the presynaptic terminal
e) provide enough depolarization in the neuron to reach threshold for firing an action
potential - ANSWER-a) generate and maintain the resting membrane potential
A protein located in the membrane of nerve cells moves glucose into the cell at the
same time as sodium ions are flowing down their concentration gradient. This would be
an example of which type of membrane protein?
a) symporter
b) antiporter
c) ion channel
d) passive diffusion - ANSWER-a) symporter
What would the voltage be across a phospholipid bilayer membrane that is permeable
only to sodium ions be if the concentration of sodium on one side of the membrane
(outside) is 100mM, and on the other side (inside) is 10mM? Assume that the system is
at equilibrium and at body temperature.
log100= 2, log 10=1, log1=0, log0.1=-1, log0.01=-2
a) +31 mV
b)+62 mV
c)-31 mV
d) -62mV - ANSWER-b) +62mV
What happens to resting membrane potential if the extracellular potassium
concentration increases from the usual 5mM to a higher concentration?
a) Nothing, the resting membrane potential would not change, only the equilibrium
potential for potassium would change
b) it would become less negative
c) it would become more negative
d) it would become 0mV - ANSWER-b) It would become less negative
Consider a neuron in which the intracellular fluid has a potassium concentration of
100mM, and the extracellular fluid has a potassium concentration of 1mM. If the cell
membrane is permeable only to potassium ions, what is the voltage across the
membrane? [assume that the system is at equilibrium and at body temperature; log
100=2, log 10=1 , log 1=0 , log0.1 = -1 , log 0.01 = -2]
a) -124 mV
b) +124 mV
c) -62 mV
d) +62 mV
e) 0 mV - ANSWER-a) -124 mV
When a neuron is at rest _________
a) the membrane permeability for potassium is higher than the membrane permeability
for sodium
