Koeppen & Stanton
Which of the following statements about the resting membrane potentials is true?
a. it is normally equal to zero volts.
b. the inside of the membrane is positively charged compared to the outside.
c. it results in part from the concentration gradient of Na+ and K+
d. the main force is a K+ voltage gated channel. - ANSWER:c. it results in part from
the concentration gradient of Na+ and K+
The resting membrane potential in a typical nerve cell is approximately
a. +70mV
b. -70mV
c. +35mV
d. 0mV - ANSWER:b. -70mV
Compared to the outside surface, the inside of a resting cell membrane is
a. positively charged
b. negatively charged
c. electrically neutral
d. continuously reversing its electrical charge - ANSWER:b. negatively charged
As the charge on the membrane of a typical neuron approaches 0- -70mV, the cell is
- ANSWER:depolarizing
The ion that plays a key role in initiating electrical signals in neurons is -
ANSWER:Na+
Which of the following is NOT involved in creating the resting potential of a neuron?
- ANSWER:resting membrane permeability of sodium ions greater than potassium
ion.
The Nerst equation predicts - ANSWER:the membrane potential resulting from
permeability to a single ion.
The total number of neurotransmitter released at the axon terminal is directly
related to a single ion. - ANSWER:the total number of action potentials.
All of the following must occur before a second action potential can begin. Except: -
ANSWER:the Na+ and K+ ions that moved in/out of the cell must move back to their
original compartments.
Which of the following does NOT influence the time necessary for a nerve impulse to
be conveyed by a particular neuron? - ANSWER:whether axon is sensory or motor
, A chemical synapse ALWAYS includes __________.
1. Axon terminal
2. Presynaptic cell
3. Synaptic cell
4. Postsynaptic cell
5. Dendrite cell - ANSWER:1, 2, 3, 4
Inhibitory neurotransmitters of the CNS act by opening ______ channels. -
ANSWER:Cl-/K+
Which of the following neurophysiology concepts are not matched up correctly? -
ANSWER:falling phase of the action potential -Na+ enters the cell.
Which of the following is NOT a known drug effect on synaptic function? -
ANSWER:change the type of neurotransmitter found in the synaptic vesicle.
The pattern of synaptic connectivity where a large number of presynaptic neurons
provide input to a single post-synaptic neuron. - ANSWER:convergence
when two or more graded potentials arrive at the trigger zone, which of the
following could happen?
a. an excitory and inhibitory signal cancel each other out.
b. two excitory stimuli may be additive
c. Two inhibitory to be additive resulting in lower excitability.
d. ----
e. A B and C - ANSWER:e. A B and C
Which of the following statements in these groups are true statements about IPSP
and EPSP?
EPSP
1. -
2. -
3. Depolarizes a neuron, increasing the likelihood of an action potential.
4. -
IPSP
5. -
6. Hyperpolarizes a neuron, decreasing the likehood of an action potential.
7. -
8. -
9. -
10. Increases permeability of chloride ions. - ANSWER:b. 3, 6, 10
Temporal summation refers to - ANSWER:additional graded potential(s) arriving
before previous ones have ceased.