Download Study Guide for Chapter 7 - Neuron Function Be familiar with the

Study Guide for Chapter 7 - Neuron Function
Be familiar with the following terms and their biological importance:
action potential (“nerve impulse”), afferent, astrocyte, axon, axonal end bulbs (synaptic end
bulbs, boutons, axon endings, synaptic knobs), bipolar neuron, blood-brain barrier, central
nervous system (CNS), chemically-gated (ligand-gated) channel, dendrite, depolarization,
efferent, electrochemical gradient, ependymal cell, equilibrium potential, excitatory postsynaptic
potential (EPSP), gated channel, glial cell, graded potential, hyperpolarization, inhibitory
postsynaptic potential (IPSP), initial segment (of neuron), interneuron (association or
internuncial neuron) leak (passive) channel, ligand, mechanically-gated channel, membrane
(transmembrane) potential, microglia, motor neuron, multipolar neuron, oligodendrocyte,
peripheral nerve, peripheral nervous system (PNS), polarized, postsynaptic cell, repolarization,
resting membrane potential, Schwann cell, sensory neuron, Na+/K+ ATPase pump, synapse,
synaptic end bulb (or bouton or synaptic knob), telodendria, threshold, unipolar neuron, voltagegated channel
How are Na+ and K+ involved in depolarization, repolarization and hyperpolarization?
Remember: Flux = P x ΔC
What two factors speed up action potentials?
What important events are occurring at the labeled portions (#1 through #4) of the graph below?
Be familiar with the meanings of the graph’s labels. (See lecture notes.)
Practice questions
1. The central nervous system (CNS) consists of the:
a. brain
b. spinal cord
d. a and b only
e. a, b and c
c. peripheral nerves
2. The relatively rare type of sensory neuron found in the eye, nose and ear is the ___ neuron.
a. bipolar
b. multipolar
c. polar
d. pseudounipolar
e. unipolar
Continued on next page
• Use the following to answer the next three (3) questions.
a. astrocytes
b. ependymal cells
d. oligodendrocytes
e. Schwann cells
c. microglia
3. These glial cells help produce cerebrospinal fluid.
4. These glial cells myelinate axons in the CNS.
5. These glial cells myelinate axons in the PNS.
6. Dendrites:
a. are found on telodendria
c. do not contain cytoplasm
b. carry information towards the cell body
d. store neurotransmitter
e. transmit action potentials
7.
a.
b.
c.
d.
e.
Efferent neurons:
are interneurons and carry information within the CNS
are motor neurons and carry information away from the CNS
are motor neurons and carry information toward the CNS
are sensory neurons and carry information away from the CNS
are sensory neurons and carry information toward the CNS
8.
a.
b.
c.
d.
The usual cause of depolarization by a neuron is:
K+ ions entering the cell
K+ ions exiting the cell
Na+ ions entering the cell
Na+ ions exiting the cell
9. Which glial cell is most important for maintaining the blood-brain barrier?
a. astrocyte
b. ependymal cell
c. microglial cell
d. oligodendrocyte
e. Schwann cell
10. Excitatory Postsynaptic Potentials:
a. always produce action potentials in the postsynaptic cell
b. bring the postsynaptic cell membrane closer to threshold
c. move the postsynaptic cell membrane further away from threshold
11. Which of the following is most important for the repolarization phase of an action potential?
a. the opening of K+ leak channels
b. the opening of voltage-gated Ca2+ channels
c. the opening of voltage-gated K+ channels
d. the opening of voltage-gated Na+ channels
12. The [Na+] is higher ___.
a. inside the cell than it is outside the cell
c. in dendrites than it is in axons
b. outside the cell than it is inside the cell
13. The inside of a neuron’s cell membrane is more ___ than the outside of the membrane.
a. negative
b. positive
c. picky
d. rude
14. When a neuron’s membrane potential reaches threshold, ___.
a. chemically-gated K+ channels open
b. chemically-gated Na+ channels open
c. the Na+ concentrations inside and outside the cell are equal
d. voltage-gated K+ channels open
e. voltage-gated Na+ channels open
1. d
2. a
3. b
4. d
5. e
6. b
7. b
8. c
9. a
10. b
11. c
12. b
13. a
14. e