Neurons, Action Potentials And Synapses

Front 1

_____: receptors detect external and internal stimuli

Back 1

Sensory

Front 2

______: the brain and spinal chord process sensory input and produce responses

Back 2

Integrative

Front 3

_______: The nervous system coordinates the activities of other systems in order to maintain homeostasis

Back 3

Homeostatic

Front 4

Anatomy professor interested in frog muscles, as well as devices for creating static electricity

Back 4

Galvani 1780

Front 5

Galvani observed that when electricity was applied to the frog leg muscle it ______

Back 5

contracted

Front 6

Galvani's observation led to theories about animals producing their own ______ and that the ______ _____ conducted this ______

Back 6

electricity; nervous system; electricity

Front 7

______ receive information from other neurons

Back 7

Dendrites

Front 8

The ____ ____ contains the nucleus and most cell organelles

Back 8

cell body

Front 9

The axon hillock integrates information collected by ______ and initiates _____ ______

Back 9

dendrites; axon potentials

Front 10

The _____ conducts action potentials away from the cell body

Back 10

axon

Front 11

____ _____ synapse with a target cell

Back 11

Axon terminals

Front 12

_____ _____ collect information from many other cells

Back 12

Bushy dendrites

Front 13

Neurons with fewer _____ process fewer inputs

Back 13

dendrites

Front 14

Some neurons _____ over a broad area, and some communicate long distances via _____ ____

Back 14

branch; long axons

Front 15

measure of the number of charge particles moving

Back 15

current

Front 16

the difference in electrical potential between two points; the force which pushes charged particles against a resistance

Back 16

voltage

Front 17

a device frequently made from a glass capillary tube which can be inserted into a cell's plasma membrane to detect voltage

Back 17

microelectrode

Front 18

the voltage observed across the plasma membrane of cells; for animal cells it is negative inside

Back 18

resting potential

Front 19

ability of a substance to pass through or across the plasma membrane

Back 19

permeability

Front 20

measure of the permeability of a charged particle; inverse of resistance

Back 20

conductane

Front 21

In an unstimulated neuron, constant difference of ____mV between outside and inside is the resting potential

Back 21

-60

Front 22

All human cells have a _____ _____ if they are healthy

Back 22

resting potential

Front 23

Only a few cell types exhibit reversible regulated changes in their membrane potentials. Some of these regulated changes are called _____ ____

Back 23

action potentials

Front 24

ion channels that respond to chemical signals

Back 24

ligand gated channels

Front 25

ion channels that respond to changes in voltage

Back 25

voltage gated channels

Front 26

Some channels ______; won't respond to signal for a set period of time

Back 26

inactivate

Front 27

Rising phase:

voltage gated sodium and potassium channels open after ____ is reached

Back 27

threshold

Front 28

Rising phase:

sodium channels open _____ and more in ______

Back 28

faster; unison

Front 29

Potassium channels open more ______ and more ______

Back 29

slowly; stochastically

Front 30

During the _____ _____ the action potential will not respond to further stimulation (absolute refractory period)

Back 30

rising phase

Front 31

Falling phase:

Sodium channels ______; won't _____ for a period of time

Back 31

inactivate; reactivate

Front 32

Falling phase:

Many ______ channels are open

Back 32

potassium

Front 33

During the _____ ____ the action potential is mostly unresponsive to further stimulus (still in absolute refractory period) Strong stimulation may trigger new ____ _____ late in this stage (_____ refractory period)

Back 33

falling phase; action potential; relative

Front 34

Recovery Phase:

The local sodium and potassium ion concentrations are restored to resting potential by the _____ and _____ ______ into the cytoplasm

Back 34

pump; passive diffusion

Front 35

Recovery phase:

The membrane potential returns to resting due to diffusion of ions _____ ____ the membrane and the diffusion of downstream sodium into the _________ region

Back 35

away from; hyperpolarized

Front 36

Action potentials travel down an _____

Back 36

axon

Front 37

An action potential is ____ or ____

Back 37

all or none

Front 38

The amplitude of an action potential is _____

Back 38

constant

Front 39

The frequency of action potentials gives information about the stimulus ______

Back 39

intensity

Front 40

_______ _______ is when the action potential hops from one node to the next

Back 40

Saltatory Conduction

Front 41

3 key steps of information flow in neuronal networks:

1. Axonal conduction of the _____ _____

2. Synaptic transmission of _____ ______ from presynaptic to postsynaptic neuron

3. Postsynaptic neuron integration of inputs to determine if _____ _____ is ______

Back 41

action potential; chemical signal; action potential is fired

Front 42

The neurotransmitter used by all vertebrate neuromuscular synapses is ______

Back 42

acetylcholine

Front 43

Resting potential is closest to the ______ equilibrium potential because it is the most permeable

Back 43

potassium

Front 44

Integration: Summation

Each neuron may have 1000 or more ____ _____, but it has only one output: an action potential in a _____ ____

Back 44

synaptic inputs; single axon

Front 45

Integration: Summation

Because postsynaptic potentials decrease in strength as they spread from the site of the synapse, a synapse at the ____ of the ____ has less influence than a synapse on the ___ ___, near the axon hillocke

Back 45

tip of the dendrite; cell body

Front 46

_____ _____ occurs when several excitatory postsynaptic potentials arrive at the axon hillock SIMULTANEOUSLY

Back 46

Spatial summation

Front 47

______ _____ means that postsynaptic potentials created at the same synapse in RAPID SUCCESION can be summed

Back 47

Temporal summation

Front 48

Glutamate is an excitatory neurotransmitter, so activation of ionotropic glutamate receptors will always result in ____ entry into the neuron and depolarization

Back 48

Na+

Front 49

The AMPA receptor is _____

Back 49

ionotropic

Front 50

The NMDA receptor is _____

Back 50

metabotropic

Front 51

The AMPA receptor allows a _____ influx of Na+ into the postsynaptic cell, whereas the NMDA receptor allows a _____, ___-_____ influx of Na+

Back 51

rapid; slower, longer-lasting

Front 52

The NMDA receptor require that the cell be somewhat ______ through the action of other receptors before their pores will open and permit ____ influx

Back 52

depolarized; na+

Front 53

When the NMDA receptors do open, they also allow ____ as well as Na+ to enter the cell. ___ ions act as second messengers in the cell an can trigger a variety of cellular changes, such as activation of certain ____ ____

Back 53

Ca2+; Calcium; protein kinases

Front 54

Glutamate can bind to both _____ and _____ receptors.

Back 54

ionotropic; metabotropic

Front 55

The ____ maintains the na+ and k+ over the long term

Back 55

pump

Front 56

Action potentials travel faster in ______ axons vs ______ and in larger ______ vs smaller _____ axons

Back 56

myelinated vs. nonmyelinated; diameter, diameter

Front 57

Summation takes place at the ____ _____

Back 57

axon hillock

Front 58

_____ is the major mechanism by which the nervous system integrates info

Back 58

Summation

Front 59

Receptors:

Is an ion channel, neurotransmitter binds to it causing a direct change in ion movement across the post synaptic cell

Back 59

Ionotropic receptor

Front 60

Receptors:

Isn't an ion channel, induces signaling cascades in the post synaptic cell that secondarily leads to changes in ion channels

Back 60

Metabotropic receptor

Front 61

Metabotropic receptors are _____ and longer lived vs ionotropic receptors that are _____ and short lived

Back 61

slower; fast