ap4 quiz 2

Question 1

1. What is not true about synapse?
   a. It is the junction only between neurons
   b. It is a physical space
   c. It mediates the flow of information
   d. The presynaptic neuron releases neurotransmitters
   e. The postsynaptic neuron has receptors for neurotransmitter to attach

Answer 1

a. It is the junction only between neurons

Question 2

2. What is/are Not true about electric synapses?
   a. Least common
   b. More in embryonic nervous tissue
   c. Are unidirectional
   d. Are slower than neurotransmitter conducted synapses
   e. Allow gradual contraction of the heart muscle

Answer 2

c. Are unidirectional
d. Are slower than neurotransmitter conducted synapses

Question 3

3. In chemical synapses, the passage of the signal is unidirectional, and electrical event of action
   potential converts into chemical event
   a. True
   b. False

Answer 3

a. True

Question 4

4. Which channels open after depolarization of presynaptic axonal terminal?
   a. Na+ channels
   b. Ca2+ channels
   c. K+ channels
   d. Cl- channels

Answer 4

b. Ca2+ channels

Question 5

5. Which statement is not fully correct in regards to events after the neurotransmitter diffuses
   across the synaptic cleft?
   a. The neurotransmitter binds with receptor protein and causes changes in shape
   b. Ion channels open creating local membrane potentials
   c. The action is always excitatory
   d. More stimulus, more synaptic cleft fusion

Answer 5

c. The action is always excitatory

Question 6

6. What is the further destiny of the neurotransmitter, released into synaptic cleft?
   a. Gets degraded by enzymes
   b. Is taken back by astrocytes
   c. Diffuses out of synapse
   d. All of the above

Answer 6

d. All of the above

Question 7

7. List 6 ways of modification of neurotransmitter effects (slide 23) with examples

Answer 7

agonist - enhances NT effect
- albuterol/epinephrine
antagonist - blocks NT effect
- antihistamines
receptor site blocked
- succinylcholine/cholinergic receptors
time in cleft prolonged / lessened
- SSRIs, cocainaaa
release blocked or enhanced
- mdma
synthesis stimulated / inhibited
- clonidine

Question 8

8. Match:
   a. Excitatory causes
   b. Inhibitory causes
   (hypopolarization, hyperpolarization, depolarization, repolarization)

Answer 8

excitatory:
depolarization

inhibitory: hyperpolarization

Question 9

9. Match:
   a. Sensory neuron
   b. Motor neuron
   c. Effector (response
   d. Mostly found in PNS
   e. Regulates skeletal muscle tone
   f. Dopamine, epinephrine, norepinephrine are
   g. Serotonin and histamine are
   h. Most common amino acid neurotransmitter (inhibitory)
   i. Most common neurotransmitter in the brain (excitatory)
   j. Major inhibitory NT in the brainstem and spinal cord
   k. Vasodilator
   l. Excitatory in PNS, CNS
   m. Neuropeptide, important in pain perception
   n. Inhibitory, toxic gas

Acetylcholine,
muscle/gland,
efferent, afferent, indolamines,
dopamine (derives from tyrosine),
Glycine,
catecholamines,
GABA,
Glutamate,
substance P,
NO,
ATP,
CO

Answer 9

9. Match:
   a. Sensory neuron
   -afferent
   b. Motor neuron
   -efferent
   c. Effector (response)
   -muscle/gland
   d. Mostly found in PNS
   -acetylcholine
   e. Regulates skeletal muscle tone
   -dopamine (derived from tyrosine)
   f. Dopamine, epinephrine, norepinephrine are
   -catecholamines
   g. Serotonin and histamine are
   -indolamines
   h. Most common amino acid neurotransmitter (inhibitory)
   -GABA
   i. Most common neurotransmitter in the brain (excitatory)
   -glutamate
   j. Major inhibitory NT in the brainstem and spinal cord
   -glycine
   k. Vasodilator-
   NO
   l. Excitatory in PNS, CNS
   -ATP
   m. Neuropeptide, important in pain perception
   -substance P
   n. Inhibitory, toxic gas
   -CO

Question 10

10. Which circuit is involved in short term memory?
    a. Converging
    b. diverging
    c. reverberating
    d. parallel after-discharge

Answer 10

c. reverberating