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Flashcards in Nervous System 2 Deck (42):
1

these function to generate and transmit messages int hr form of nerve impulses or action potentials from one part of the body to another

neurons/nerve cells

2

neuron sending the message

presynaptic cell

3

the other cell besides the presynaptic cell

postsynaptic cell

4

neuronal processes that receive input

dendrites

5

sends impulses (generates and transmits electrical impulses to postsynaptic cell`)

axon or nerve fiber

6

cytoplasm of axon

axoplasm

7

plasmalemma of axon

axolemma

8

small raised area between cell body and beginning of an axon

axon hillock

9

located just beyond the cekk body and beginning of an axon

initial segment

10

neurons form connections between their effectors called

synapses

11

an electrical/ chemical juntion or point of close contact between 2 neurons or a neuron and effector cell

synapse

12

response to a generated and conducted electrical impulse that travels along the length of its axon

action potential/ nerve impulse

13

measure of potential energy generated by separated charge

voltage

14

voltage measured between 2 points

potential difference

15

flow of electrical charge between 2 points

current

16

hindrance to charge flow

resistance

17

substance with high electrical resistance

insulator

18

substance with low electrical resistance

conductor

19

potential difference across a cell membrane

transmembrane potential

20

an unequal distribution of charge across a cell membrane in which the inside membrane is slightly negatice due to a slight excess of negatively charged ions and proteins

transmembran potential

21

region that forms a molecular gate and changes shape to open and close to specific signals

gated channels (some are chemically gated)

22

protein channels has a specific area that acts as a receptor (binding site) for a specific type of ligand

chemically gated channels

23

channel where sodium and potassium are being transported simultaneously in opposite directions

antiport

24

channels that open and close in response to changes in the membrane potential

voltage gated channels

25

channels that open in response to physical deformation of the receptor

mechanically gated channels

26

example of mechanically gated channels

Meissners Pacinian corpuscles found in integument

27

channles that do not respond to signals and are always open (selective as to the type of ion is allowed to pass through)
ex..

leakage or non gated channels
ex K and Na ion leakage channels

28

when ions are diffusing quickly across the membrane after gated channels are open, what creates electrical currents an voltage changes across the membrane

electrochemical gradients

29

during chemical concentration gradients, what do the ions do

diffuse passively from higher concentration area to a lower concentration area; moving towar an area with opposite electrical charge

30

transmembrane potential of a cell at rest, all neural activities begin with a charge from this

resting potential

31

temporary. localized change in resting potential due to typical stimulus, decreases w/ distance from the stimulus

graded potential

32

electrical event involving one location of axonal membrane, can be triggered by large graded potential, propagated along axon surface toward synaptic terminals

action potential

33

potential difference between 2 points can be measured by using what

voltmeter

34

how is potential across the membrane of a neuron measured

by sticking a microelectrod inside the neuron and other in the interstitial fluid

35

average potential difference of a neuron at rest

-70 mV (neg means cytoplasmic side of membrane is neg)

36

which is most permeable: Na or K

potassium, 75x more

37

go back to slide

13

38

when a stimulus causes the membrane potential to increase (becomes more neg)

hyperpolarization

39

what is essential in initiating action potentials which are the long distance signals

graded potential

40

total amplitude during action potential

100mV`

41

what opens when sodium ions rush to the cell

sodium channels

42

revisit slide 17

slide 17