Exam 2 Lecture - Synapse

Question 1

What is an axodendritic synapse?

Answer 1

a synapse that is connecting to the dendrites

Question 2

What is an axosomatic synapse?

Answer 2

synapse that is connecting to the soma

Question 3

What is an axoaxonic synapse?

Answer 3

a synapse that is connecting to the axon

Question 4

What are the presynaptic structures of a synapse?

Answer 4

synaptic vesicles with a neurotransmitter and a presynaptic membrane

Question 5

Where is the synaptic cleft located?

Answer 5

in between the presynaptic structures and postsynaptic structures

Question 6

What are the postsynaptic structures of a synapse?

Answer 6

postynaptic membrane and a ligand-gated receptor

Question 7

What are the excitatory neurotransmitters of the CNS?

Answer 7

glutamate and acetylcholine

Question 8

What is glutamates receptor?

Answer 8

GluR

Question 9

What is acetylcholines receptor?

Answer 9

AChR

Question 10

What are the excitatory neurotransmitters of the PNS?

Answer 10

acetylocholine

Question 11

What are the inhibitory neurotransmitters of the CNS?

Answer 11

Glycine and GABA

Question 12

Where are synapses located?

Answer 12

Where the terminal branches meet either the cell body, dendrites, or axon

Question 13

True or False: a neuron gets a signal from only one other neuron

Answer 13

False

Question 14

How do tetanus and strychnine interfere with motor function?

Answer 14

they prevent the release of glycine and GABA from inhibitory neurons and Renshaw cells

Question 15

What are the clinical signs of strychnine?

Answer 15

over activity of extensor muscles

Question 16

How long does the tetanus toxin stay bound?

Answer 16

for over 4 weeks

Question 17

What are the clinical signs of teanus toxin?

Answer 17

over activity of extensor muscles

Question 18

How does the excitatory synapse generate membrane depolarization?

Answer 18

• releases excitatory neurotransmitters
• neurotransmitters bind to their receptors
• receptors open ligand-gated ion channels for Na
• Na inflow
• generation of depolarizing excitatory postsynaptic membrane potential (ESPS)

Question 19

How does the inhibatory synapse generate membrane hyperpolarization?

Answer 19

• releases inhibitory neurotransmitter
• neurotransmitters binds to their receptors
• receptors open ligand-gated ion channels for Cl
• Cl influx
• generates hyperpolarizing inhibitory postsynaptic membrane potential (IPSP)

Question 20

What is the difference between a graded potential and an action potential?

Answer 20

Action potentials are either all or nothing

Graded potentials vary in size, they aren’t either all or nothing

Question 21

Where is the axon hillock located in a neuron?

Answer 21

between the cell body and the axon

Question 22

What roll does the axon hillock play in generating action potential?

Answer 22

generates AP when sum of ESPS and IPSP goes over the threshold membrane potential

Question 23

What are the two mechanisms that determine membrane potential at the axon hillock?

Answer 23

spatial and temporal summation

Question 24

What is spatial summation?

Answer 24

the summation of multiple separate signals arriving at different synaptic sites simultaneously

Question 25

What is temporal summation?

Answer 25

the summation of multiple signals arriving at a single synaptic site