Download Chapter 11 Practice Questions

Biology 2121 - Practice Questions
Chapter 11 - Neurophysiology
Name___________________________________
MATCHING. Choose the item in column 2 that best matches each item in column 1.
Match the following:
1) Neurotransmitters are released at
the ________.
A) Axon terminal
1) _______
2) The rough ER of the cell.
B) Dendrites
2) _______
3) Conducts impulses toward the
C) Axon
3) _______
nerve cell body.
D) Nissl bodies
4) Conducts impulses away from the
4) _______
nerve cell body.
Match the following:
5) Period during which the neuron
cannot respond to a second stimulus,
no matter how strong.
A) Depolarization
5) _______
B) Absolute refractory period
6) The interior of the cell becomes less
6) _______
negative due to an influx of sodium
ions.
7) The specific period during which
A) Relative refractory period
7) _______
potassium ions diffuse out of the
neuron due to a change in
membrane permeability.
B) Repolarization
8) Called a nerve impulse when
C) Action potential
8) _______
transmitted.
9) An exceptionally strong stimulus
9) _______
can trigger a response.
Match the following:
10) Numerous nerve impulses arriving
at a synapse at closely timed
intervals exert a cumulative effect.
A) Subthreshold stimulus
B) Threshold stimulus
10) ______
11) Stimulation of a postsynaptic
11) ______
neuron by many terminals at the
same time.
C) Spatial summation
12) An insufficient stimulus.
D)
12) ______
Temporal summation
13) Any stimulus below this intensity
13) ______
will result in no response in a
neuron.
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the
question.
14) That part of the nervous system that is voluntary and conducts impulses from the CNS 14) ____________
to the skeletal muscles is the ________ nervous system.
15) ________ are found in the CNS and act as the glue that binds axons and blood vessels
15) ____________
to each other.
16) The gap between Schwann cells in the peripheral system is called a(n) ________.
16) ____________
17) The most common synapse in embryonic nervous tissue is the ________.
17) ____________
18) ________ potentials are short-lived, local changes in membrane potential that can be
18) ____________
either depolarized or hyperpolarized.
19) ________ is a disease that gradually destroys the myelin sheaths of neurons in the CNS,
19) ____________
particularly in young adults.
20) When one or more presynaptic neurons fire in rapid order it produces a much greater
20) ____________
depolarization of the postsynaptic membrane than would result from a single EPSP;
this event is called ________ summation.
21) Define neurotransmitter. Name two amino acid neurotransmitters, two catecholamines,
21) ____________
and two peptides.
22) Imagine a neuron that has several hundred axonal knobs impinging on it. The majority
22) ____________
of these axonal knobs are shown to be "firing." However, the neuron in question does
not transmit an impulse. Give a valid explanation of why this could occur.
23) Why does a hyperpolarization phase generally follow a repolarization phase in an
acti on potential?
23)
____________
24) What are the basic divisions of the peripheral nervous system?
24) ____________
1)
2)
3)
4)
A
D
B
C
5)
6)
7)
8)
9)
B
A
B
C
A
10)
11)
12)
13)
D
C
A
B
14) somatic
15) Astrocytes
16) node of Ranvier
17) electrical synapse
18) Graded
19) Multiple sclerosis (MS)
20) temporal
21) Neurotransmitters are chemical signals used as a means of communication. GABA and glycine are amino acid
neurotransmitters; dopamine and norepinephrine are catecholamines; and endorphin and enkephalin are peptide
transmitters.
22) Both excitatory and inhibitory potentials impinge on neurons. Inhibitory postsynaptic potentials (IPSPs) are "firing,"
but due to the neurotransmitter released and its action, the postsynaptic neuron is inhibited from "firing"
(hyperpolarized).
23) Immediately after an action potential the potassium gates, being slow gates which do not respond to change in the
electrical charge, allow additional K+ ions to flood into the cell. These K+ ions decrease the positive ion
concentration momentarily below the normal -70mV and thus hyperpolarize the cell.
24) Sensory and motor divisions. Motor has two divisions: the somatic and autonomic. The autonomic has two
divisions: the sympathetic and parasympathetic.