Oct. 13: 2.2

Question 1

How many synaptic inputs does a neuron receive in chemical synaptic transmission?

Answer 1

tens of thousands to hundreds of thousands

Question 2

Compare versatility of chemical to electrical synapses

Answer 2

Chemical is more versatile:
FIRES melt Plastic
fast synapses
inhibitory tsmission
regulation
excitatory tsmission
slow synapses
plasticity

Question 3

Experiment demonstrating existence of chemical synapses/ neurotransmitters

Answer 3

Otto Loewi

Stimulate one frog heart electrically through vagus nerve, then add perfusate to another heart. This heart slows down.

Question 4

Speeds up heart rate

Answer 4

sympathetic stimulation

Question 5

Slows down heart rate

Answer 5

parasympathetic stimulation/ vagus nerve

Question 6

Why heart beats by itself in saline

Answer 6

pacemaker cells

Question 7

chemical which slows down heart rate

Answer 7

acetylcholine

Question 8

Types of NT receptors in chemical tsmission

Answer 8

ionotropic

metabotropic

Question 9

Effects of metabotropic receptors

Answer 9

cascade of biochemical events culminating in the opening or closing of certain ion channels and a change in membrane potential

Question 10

PSD

Answer 10

post-synaptic density

proteins needed for NT clustering and synaptic function

Question 11

Active zones

Answer 11

where vesicles are docked at presyn membrane

Question 12

calcium entry at terminals triggers

Answer 12

fusion of vesicles with membrane

Question 13

EPSP produces _____ current

Answer 13

Inward

“Inwardly excited, outwardly inhibited”

Question 14

Outward current leads to

Answer 14

hyperpolarization

Question 15

example of effect EPSP might have w/o reaching threshold

Answer 15

effects voltage-gated Ca++ channels which then changes calcium signalling inside cell

Question 16

Fast synaptic transmission describes transmission involving _____ receptors

Answer 16

ionotropic

Question 17

neuromuscular junction makes good prep for study because

Answer 17

most neurons form synapses at spines of dendrites, which are so small an indirect reading is necessary

Question 18

nicotinic versus muscarinic acetylcholine receptors

Answer 18

nicotinic are ionotropic

muscarinic are metabotropic

Question 19

Targets acetylcholinesterase

Answer 19

Organophosphates such as nerve gas and insecticides

Question 20

When acetylcholine is broken down, what happens to the choline?

Answer 20

recycled back into presyn cleft b/c of choline gradient

Question 21

Curare blocks

Answer 21

nicotinic ACh receptors

Question 22

Type of ACh receptors at neuromuscular junction

Answer 22

nicotinic

Question 23

depolarizations of skeletal muscle fibers are called

Answer 23

EPPs

Question 24

Vesicle cycle time: _____

Answer 24

1 minute

Question 25

Delay between excitation of presynaptic terminal and tsmission

Answer 25

1ms

Question 26

Time required for budding phase of vesicle cycle

Answer 26

10-20sec