Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology 116 > Action Potentials > Flashcards

Action Potentials Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

NS functions

A

detect stimuli + any sort of change that occurs inside or outside body; respond to stimuli and carry out an action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

key components of NS

A

CNS: brain + spinal cord; PNS: sensroy receptors + nerves for communication singals btwn CNS + rest of body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

neuron

A

basic functional unity of NS; variety of shapes + size depending on fuction; characterized by cell body + cytoplasmic extensions that protrube out of neuron; dendrite, nerve, axon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

neuron function

A

conduct messages via electrical singnal + integration of message

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

cell body

A

location of usual organelles (nucleus, mito, golgi, etc)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

dendrite function

A

(tree branch) recieve info from env or other neurons and send signals to cell body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

nerve

A

comprised of axons of many neurons held together by connective tissue; axons travel together to whatever part of body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

axon

A

usually one long one; transmit neural impulse away from cell body to another nurons; end of axon = branches, tips of branches = synaptic terminals @ opp end of cell body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

effector

A

part of org that produces response to stimuli; produces “effect”; ex: muscles, glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

axon hillock

A

cone shaped base of axon; region where axon begins extending away from cell body; location where signals will be generated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

3 stages of NS info processing

A

(1) sensory input (2) integration (3) motor output

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

sensory input

A

stage 1 of NS info processing; detecting stimulus; sensory neuron = afferent neuron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

afferent neuron

A

recieve sensory stimuli; conduct info toward processing center

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

integration

A

stage 2 of NS info processing; sensory input sorted out and interpreted in processing center (was it visual? auditory? now what?) human brain = 90% interneurons)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

motor output

A

what is appropriate response to stimulus?; motor neuron = efferent neurons; transmit info from processing center and associate w appropriate responses to appropriate effector; part of org that produces response: muscles + glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

membrane potential

A

all animal cells w selectively permeable membrane; only excitable cells have ability to generate rapid changes in mem pot

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

selectively permeable membrane

A

some things geet in somethings don’t; polarity btwn inside + outside of cell so mems are “polarized”; charged diff btwn inside vs outside = neg mem pot; cytosol of cell = neg charge vs. extracellular fluid env on outside; mem pot = pot to do work actions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

voltage

A

unit to measure mem pot

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

voltmeter

A

position electrode inside cell + outside cell; reference electrode, second electrode; measure charge diff btwn inside vs outside of cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

reference electrode

A

outside of cell

21
Q

second electrode

A

inside of cell

22
Q

resting potential

A

cell mem of axon at rest; not excited; RP = -70mV

23
Q

maintaining RP

A

sodium-potassium pump; ion channels

24
Q

sodium potassium pump

A

used to maintain RP; mem protein of cell along pm of cell body, dendrite, axon (entire neuron); one pump cycle: 3 Na+ ions move out and 2 K+ ions move in via active transport against concen gradient (needs ATP)

25
Q

ion channels

A

pore in pm allow ions to diffuse across pm; any net movement of either pos of neg charges generates mem pot; K+ channels always open (leaky) = diffuse from inside to outside to maintain neg RP; many K+ channels more than Na+; 100x more permeable to K+; build up of pos charge on outside relative to inside and creates neg RP = -70mV bc neg inside vs pos outside

26
Q

env factors that change RP

A

RP can be changed via sitmulus; chem, pressure, light

27
Q

threshold

A

most are -55 mV; results in action potential

28
Q

hyperpolarization

A

mem pot moves below RP; more neg than RP; decreases neuron’s ability to generate a neural impulse; inhibitory; very important

29
Q

graded potentials

A

shifts in mem pot; magnitube varies w strength of stimulus bc greater the stimulu greater change in mem pot; eventually decay/die out sometimes induce small electrical message that won’t propagate (time +source)

30
Q

deploarization

A

mem pot becomes more pos; above RP

31
Q

action potentials

A

mem pot shifts significantly; massive change in voltage; deploarizaiton causes mem pot to reach -55mV threshold

32
Q

voltage gated ions channels

A

part of AP; mem proteins control passage of specific ions (specific gates for specific ions) they open/close based on changes in voltage; reg by changes in voltage that control shape of protein that closes in one shape and open in another shape; facillitate diffusion allows ions to follow concern gradient (no ATP, via protein)

33
Q

AP chain of events

A

neurons at RP no excitment all VG Na+ and VG K+ channels close + no ion movement; VG Na+ channel open; Na+ rushes into axon; mem depolarizes (less neg); gets closer to -55mV (threshold); magnitude of change in pot depends on stimulus strength: small stimulus won’t reach -55mV bc few channels open but strong stimulus many channels open so it reaches -55mV

34
Q

AP steps

A

rising potential, falling phase, undershoot

35
Q

rising potential

A

AP; mem become very permeable to Na+ and most of VG Na+ channels open so Na+ rushes down gradient into cell; VG K+ channels closed so K+ stays inside to cause depolarization where inside cell = pos vs outside cell; causes +35mV spike in mem pot and reaches max deploraized state

36
Q

falling phase

A

AP; most VG Na+ channels close so mem imperm to Na+; neuron = refracotry period so no other action pot possible bc Na+ channels close and won’t open until they reset; VG K+ channels open slowly after threshold and fully open @ peak depolarization (+35mV); K+ rush outside cell (follow concen grad)

37
Q

undershoot

A

AP; VG Na+ channels close and some VG K+ channels open; hyperpolarizaiton bc mem pot more neg than RP; eventually VG K+ channels close; mem returns to RP = -70mV

38
Q

all or none event

A

whenever action pot steps happen it is always same process/outcome; intensity of sensation varies + depends on # neurons stimulated and freq of stimulation; we can differentiate diff levels of intensity

39
Q

AP conduction

A

series of APs move as a signal along axon; prob: AP happens @ only one location on axon; need to move message down whole axon; so use conduction

40
Q

AP via conduction

A

AP begins @ axon hillcok and wave of depolarization spread in one direction; as voltage shifts in one region it spreads to nearby VG Na+ channels further along axon; only one way stimulation “down” the axon away from cell body; wave-like stimulation down axon via VG Na+ channel openings leading to cont AP

41
Q

myelin sheath

A

electrical insulation that surrounds axon; produced by 2 types of glial cells: oligodendrocytes (CNS) and schwann cells (PNS)

42
Q

axon plasma mem

A

rich in myelin; white colored lipid produced by glial cells wrapped around axon; structure: internodes, nodes of ronvier, unmylinated axons

43
Q

internodes

A

regions of axons covered by glial cells

44
Q

nodes of ronvier

A

gaps in myelin sheath

45
Q

unmylinated axons

A

grey matter, cont conduction, every spot along neuron depolarized/repolarized; hard work

46
Q

AP conducation structure

A

myelinated axons = white matter; faster message tranmissions more E eff; @ nodes of ranvier: no myellin, high concen of VG Na+ and VG K+ channel; lots of depolarization = APs; APs jump node to node via saltatory conduction

47
Q

saltatory conduction

A

APs jump node to node

48
Q

multiple sclerosis

A

myelin sheath gradually deteriorates; replaced w scare tissue; slow neural transmission + loss of coordination

Biology 116 (27 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions