Tissues and Cells of the Nervous System: A & P Exam 3

0.0(0)
studied byStudied by 0 people
learnLearn
examPractice Test
spaced repetitionSpaced Repetition
heart puzzleMatch
flashcardsFlashcards
Card Sorting

1/51

encourage image

There's no tags or description

Looks like no tags are added yet.

Study Analytics
Name
Mastery
Learn
Test
Matching
Spaced

No study sessions yet.

52 Terms

1
New cards

endocrine system

communicates by means of chemical messengers secreted into the blood

2
New cards

nervous system

employs electrical and chemical means to send messages from cell to cell

3
New cards

electrophysiology

study of cellular mechanisms for producing electrical potentials and currents, basis for neural communication and muscle contraction

4
New cards

electrical potential

a difference in concentration of charged particles between one point and another

5
New cards

electrical current

a flow of charged particles from one point to another

6
New cards

resting membrane potential

exists because of unequal electrolyte distribution between extraceullar fluid and intracellular fluid,

7
New cards

potassium

greatest influence on RMP, leaks out until electrical charge of cytoplasmic anions attracts it back in and equilibrium is reached

8
New cards

cytoplasmic anions

cannot escape due to size or charge

9
New cards

sodium

membrane not very permeable to, leakage of makes RMP slightly less negative

10
New cards

Na+/K+ pump

moves 3 Na+ out for every 2 K+ it brings in, works continuously

11
New cards

local potentials

changes in membrane potential of a neuron occurring at and nearby the part of the cell that is stimulated

12
New cards

action potential

dramatic change in membrane polarity produced by voltage-gated ion channels

13
New cards

trigger zone

where action potential is generated

14
New cards

nondecremental action potential

do not get weaker with distance

15
New cards

irreversible action potential

once started, goes to completion and cannot be stopped

16
New cards

refractory period

the period of resistance to stimulation

17
New cards

absolute refractory period

no stimulus of any strength will trigger AP, lasts as long as Na+ gates are open, then inactivated

18
New cards

relative refractory period

K+ gates still open and any effect of incoming Na+ is opposed by the outgoing K+

19
New cards

unmyelinated fibers

have voltage-gated channels along their entire length, can’t skip an axon, take longer

20
New cards

myelinated fibers

conduct signals with saltatory conduction, signal seems to jump from node to node, fast

21
New cards

nodes of ranvier

gaps in the myelin sheath coating on the neural axon, contain many voltage-gated ion channels

22
New cards

synaptic cleft

gap between neurons

23
New cards

neurotransmitters

molecules that are released when a signal reaches a synaptic nob that binds to a receptor on another cell and alter that cell’s physiology

24
New cards

acetylcholine

neurotransmitter, in a class by itself, formed from acetic acid and choline

25
New cards

Amino acid

neurotransmitter, include glycine, glutamate, aspartate and GABA

26
New cards

Monoamines

neurotransmitter, synthesized from amino acids by removing the COOH group while retaining the -NH2 (amino) group

27
New cards

neuropeptides

neurotransmitter, chains of 2 to 40 amino acids, stored in secretory granules, some function as hormones

28
New cards

gases

nitric oxide and carbon monoxide, synthesized as needed rather than stored

29
New cards

neuromodulators

chemicals secreted by neurons that have long term effects on groups of neurons

30
New cards

neuropeptides

chains of amino acids that can act as neuromodulators

31
New cards

axonal transport

two-way passage of proteins, organelles and other material along an axon

32
New cards

anterograde transport

movement down the axon away from neurosoma

33
New cards

retrograde transport

movement UP the axon Towards the neurosoma

34
New cards

kinesin

motor proteins in ANTEROGRADE transport

35
New cards

dynein

motor proteins in RETROGRADE transport

36
New cards

fast axonal transport

rate of 20 to 400 mm/day, fast anterograde and retrograde transport

37
New cards

slow axonal transport

0.5 to 10 mm/day, ALWAYS anterograde

38
New cards

neuroglia cells

protect neurons and help them function, binds neurons together

39
New cards

oligodendrocytes

form myelin sheaths in CNS that speed signal conduction

40
New cards

Ependymal cells

line internal cavities of the brain, secrete and circulate cerebrospinal fluid

41
New cards

microglia

wander through CNS looking for debris and damage, develop from white blood cells

42
New cards

astrocytes

most abundant glial cell in CNS covering brain surface and most non synaptic regions of neurons in the gray matter, form supportive framework, form blood-brain barrier, convert glucose to lactate and supply this to neurons

43
New cards

Schwann cells

cells that produce a myelin sheath, envelop nerve fibers in PNS

44
New cards

satellite cells

surround the neurosomas in ganglia of the PNS, provide electrical insulation around the neurosoma

45
New cards

myelin sheath

insulation around a nerve fiber, helps speed up electrical impulses

46
New cards

myelination

production of the myelin sheath,

47
New cards

neurilemma

thick, outermost coil of myelin sheath,

48
New cards

endoneurium

external to neurilemma, thin layer of fibrous connective tissue, insulates 1 axon

49
New cards

internodes

myelin-covered segments from one gap to the next

50
New cards

initial segment

short section of nerve fiber between the axon hillock and the first glial cell

51
New cards

trigger zone

the axon hillock and the initial segment, play bid role in initiating a nerve signal

52
New cards

nerve growth factor

protein secreted by a gland, muscle or glial cells and picked up by the axon terminals of neurons