Lecture 8 VGSC, Synapses

Question 1

TTX

Answer 1

Blocks VGSC - puffersih

Question 2

Batrachotoxin

Answer 2

opens channel irregularly - frogs

Question 3

µ-Conotoxin

Answer 3

blocks channel - snails

Question 4

Patch clamp

Answer 4

neural membrane removed via recording electrode tip using suction
Channels present are stimulated and individual ion currents measured

Question 5

AP must propagate signal along

Answer 5

entire length of axon

Question 6

AP are

Answer 6

self propagating; travel in only one direction

Question 7

Nerve impulse

Answer 7

AP propagation down axon

Question 8

conduction speed

Answer 8

rate of propagation influenced by both axon diameter and myelination

Question 9

Axon with larger diameter

Answer 9

faster conduction speed - lower resistance

Question 10

Myelinated neurons

Answer 10

fast signals through salutary conductions

Question 11

Continuous conductions

Answer 11

Unmyelinated axon every section of axolemma from trigger zone to axon terminal must propagate action potentials

Question 12

Saltatory conduction

Answer 12

the insulating properties of the myelin sheath increases efficiency and speed of signal conduction

Question 13

AP only depolarize

Answer 13

nodes of reviver; jumps from node to node

Question 14

channel rhodosin

Answer 14

gene is inserted into larger DNA of specific populations

Question 15

Fiber optic cable

Answer 15

used to stimulated and modulate target control

Question 16

presynaptic neuron

Answer 16

neuron sending message from its axon terminal

Question 17

Postsynaptic neuron

Answer 17

neuron receiving message from presynaptic neuron at body, axon or dendrites

Question 18

electrical synapses

Answer 18

occurs between cells electrically couple via gap junctions

Question 19

Axolemmas of each cell in synapses are nearly touching;

Answer 19

gap junction align channels forming pores that ions or other small substances can flow through

Question 20

Chemical synapse

Answer 20

Neurotransmitter signal between pre/postsynapse
- more efficient and used
convert AP into chemical signals

Question 21

synaptic vesicle

Answer 21

transmit signals from pre/postsynaptic neurons through exocytosis

Question 22

synaptic cleft

Answer 22

Separates presynaptic and postsynaptic neurons in chemical sequence

Question 23

synaptic delay

Answer 23

time gap between arrival of AP at axon terminal and effect on postsynaptic membrane

Question 24

the most neurotransmitter released…

Answer 24

stronger response at postsynaptic neuron

Question 25

AP in presynaptic neuron triggers

Answer 25

opening VG calcium ion channels in axon termianls

Question 26

influx of calcium ions

Answer 26

causes synaptic vesicle to release neurotransmitter into synaptic cleft