Summer physiology- 7 hw

action potentials are described as:______

all or none

found at the neuromuscular junction

acetylcholine

reward and motivation

dopamine

major inhibitory NT

GABA

major excitatory NT

glutamate

hyperpolarizing graded potential

IPSP

rapid signals from one synapse

temporary summation

depolarizing graded potential

EPSP

signals from multiple synapses

spatial summation

contains nucleus

cell body

initiates action potentials

axon hillock

receives incoming signals

dendrites

conduct impulses away

axon

chemical synapses are faster than electrical synapses.

false

chemical synapses use:____

neurotransmitters

stronger stimuli are coded by:_____

more frequent action potentials

resting membrane potential is primarily determined by:____

K permeability

synaptic plasticity refers to changes in synapse stregth.

true

neurons can easily regenerate in the CNS.

true

the functional unit of the nervous system is the:____

neuron

GABA is an inhibitory neurotransmitter.

true

long-term potentiation is associated with:____

memory and learning

cell type that produces myelin in the PNS:____

schwann cells

structure that receives incoming signals

dendrites

absolute refractory period occurs because:____

Na channels are inactivated

EPSPs cause:__

depolarization

synapses are defined as:___

functional connections between cells

glial cells are more numerous than neurons.

true

the Na/K pump moves:___

3 Na out, 2 K in

IPSPs cause:_____

hyperpolarization

calcium is required for neurotransmitter release.

true

neurotransmitter release is triggered by:_____-

CA+ influx

temporal summation involves:___

rapid signals at one synapse

during repolarization:_____

K leaves the cell

EPSPs have a refractory period.

false

depolarization occurs when:___

Na enters the cell

myelin increases conduction speed.

true

the threshold for an action potential is reached when:_____

Na channels open rapidly

saltatory conduction occurs in:____

myelinated axons

depolarization makes the membrane more negative.

false

action potentials decrease in strength as they travel.

false

spatial summation involves:____

multiple synapses at once