S2_L3: The Synapse

Question 1

TRUE OR FALSE: An EPSP can always produce an action potential

Answer 1

False

Question 2

TRUE OR FALSE: As an EPSP or IPSP travels from dendrites to soma, its magnitude decreases

Answer 2

True

Question 3

ACh vesicles conglomerate along ___

Answer 3

Active Zones
-> where small vesicles are located

Question 4

What is a functional connection between a nerve and a 2nd cell?

Answer 4

Synapse

Question 5

What is the cell before the synapse?

Answer 5

Presynaptic cell

Question 6

What do you call the space in the synapse?

Answer 6

Synaptic cleft

Question 7

What are stored in synaptic vesicles?

Answer 7

Neurotransmitters (ligands)

Question 8

Which are parts of the small synaptic vesicles?
A. GABA
B. Oxytocin
C. Epinephrine
D. Both A and C
E. All of the above

Answer 8

D. Both A and C

Question 9

What does the neurotransmitter activate in the
postsynaptic cell?

Answer 9

Receptor-ion channel

Question 10

The term for the process of stimulating the postsynaptic cell once at multiple sites

Answer 10

Spatial summation

Question 11

The term for the process of stimulating the postsynaptic cell multiple times at one site

Answer 11

Temporal summation

Question 12

The principle where 1 nerve has 1000 branches and 1 nerve has axodendritic connections.

Answer 12

principle of divergence

Question 13

The Golgi bottle neuron, Renshaw cell, and Interneurons are all ___ neurons.

Answer 13

inhibitory

Question 14

Which of the following will NOT transmit the impulse?
A. Axo-somal
B. Axodendritic
C. Axo-axonic
D. Dendrodentritic

Answer 14

D. Dendrodentritic

Question 15

High Na+ influx will cause what type of postsynaptic potential?

Answer 15

Excitatory Postsynaptic Potential

Question 16

Opening of K+ channels, high Cl- conductance, and closure of Na+ or Ca++ channels will cause what type of postsynaptic potential?

Answer 16

Inhibitory Postsynaptic Potential

Question 17

Small synaptic vesicles with a brownish / blackish dense central core contain __?

Answer 17

catecholamines

Question 18

TRUE OR FALSE: The electrical synapse is always excitatory.

Answer 18

True

Question 19

TRUE OR FALSE: In chemical synapses, the conduction is one-way conduction.

Answer 19

True

Question 20

TRUE OR FALSE: Every part of nerve can receive and conduct impulses.

Answer 20

True, because it’s an excitable cell

Question 21

The principle where 1 nerve receives 10,000 synaptic inputs (2,000 on the soma and 8,000 on the dendrites).

Answer 21

principle of convergence

Question 22

TRUE OR FALSE: There is many mitochondria present in the presynaptic terminal.

Answer 22

True

Question 23

Large synaptic vesicles with a dense core contain __?

Answer 23

neuropeptides

Question 24

Ca2+ attaches to SNAP 25 and SNAP 25 elicit chain reaction and attaches all these protein complexes until ___ will pull the synaptic vesicle toward the plasma membrane.

Answer 24

synaptobrevin

Question 25

A very potent muscle paralyzer that inhibits synaptobrevin, thus there is no protein to pull the synaptic vesicle toward the plasma membrane.

Answer 25

Botulinum toxin

Question 26

Conglomeration of receptors for neurotransmitters that immediately receive ligands, resulting in immediate transmission

Answer 26

Dense bars

Question 27

In the process of an EPSP, the influx of ___ is the signal for exocytosis of neurotransmitters into the synaptic cleft and it will be received by the receptors in the post-synaptic cell

Answer 27

calcium

Question 28

Determine the corresponding descriptions of direct & indirect inhibition 1. Opens a different type of ligand-gated channel 2. Effects of previous postsynaptic cell discharge 3. Inhibitory Postsynaptic Potential 4. During the refractory period and during the hyperpolarized stage A. Direct Inhibition B. Indirect Inhibition

Answer 28

1. A 2. B 3. A 4. B

Question 29

TRUE OR FALSE: Opening of K+ channels, high Cl- conductance, and decrease in Ca++ entry are the mechanisms for presynaptic inhibition.

Answer 29

True

Question 30

TRUE OR FALSE: To produce more EPSPs in the post-synaptic cell, presynaptic facilitation must occur. This happens by prolonging the AP in the presynaptic cell, where more voltage gated potassium channels open and more calcium enters, resulting in more EPSPs.

Answer 30

True

Question 31

This neurotransmitter increases cAMP and acts via the secondary messenger system which forces the K+ channels to close early during repolarization. This results in a prolonged AP and presynaptic facilitation.

Answer 31

Serotonin

Question 32

The state wherein a neuron is on the verge of an action potential and needs 1 more signal to finally discharge.

Answer 32

Subliminal fringe