C2.2 - Neural Signaling

Question 1

neurons

Answer 1

cells within the nervous system that carry electrical impulses

Question 2

nerve impulse

Answer 2

electrical signal passed between two cells

Question 3

membrane potential

Answer 3

voltage created by an imbalance of charges on either side of membrane

Question 4

neuron at rest

Answer 4

negative charge (-70MV)
sodium ions outside cell

Question 5

depolarization

Answer 5

membrane potential goes from negative to positive

Question 6

repolarization

Answer 6

membrane potential goes from positive to negative

Question 7

what causes repolarization/depolarization

Answer 7

movement of ions during action potential

Question 8

process of neurotransmission along neurons

Answer 8

voltage gated sodium ions open
sodium ions diffuse into cell (facilitated)
depolarization
voltage gated sodium ions close
voltage gated potassium ions open
potassium ions diffuse out
repolarization
sodium potassium pump re-establishes resting potential
actively pumping sodium out and potassium in

Question 9

role of ATP in sodium potassium pump

Answer 9

energy to facilitate active transport of K and Na in and out of cells

Question 10

nerve impulses along neuron are…

Answer 10

self propogating

Question 11

meaning of self-propogating

Answer 11

depolarization in one part triggers depolarization in next due to opening of voltage gated channels

Question 12

CNS

Answer 12

central nervous system

Question 13

CNS components

Answer 13

brain & spinal cord

Question 14

CNS job

Answer 14

receives signals from receptors then interpret & process sensory info

Question 15

sensory neuron

Answer 15

carry info to CNS

Question 16

motor neuron

Answer 16

carry info to effector organ

Question 17

nerve

Answer 17

group of neurons

Question 18

axons

Answer 18

relatively long single fiber

Question 19

dendrite

Answer 19

multiple short fibers

Question 20

job of axon and dendrite

Answer 20

send electrical impulses to travel down fibers

Question 21

myeline sheath

Answer 21

made of schuann cells

Question 22

job of myeline sheath

Answer 22

wrap around axon and act as insulator
no ion movement in insulated areas

Question 23

impact of myeline sheath on speed

Answer 23

impulse jumps from one node to next due to insulation, increases speed bc impulse travels faster, movement of ions only in nodes, less ATP needed

Question 24

nerve impulses can be sped up through…

Answer 24

increase in diameter, myelination

Question 25

synapse

Answer 25

gap between cells through which signals are passed by neuro transmitter

Question 26

synaptic neurotransmission types

Answer 26

neuron to neuron neuron to effector organ neuron to sensory organ

Question 27

release of neurotransmitter from presynaptic membrane

Answer 27

action potential reaches end of presynaptic neuron voltage gated calcium ion channel opens calcium ion enter presynaptic neuron (facilitated) calcium ions force vesicles to fuse with membrane neurotransmitters released to synapse neurotransmitters diffuse across synapse bind to receptors on postsynaptic membrane sodium ion channel open generates action potential neurotransmitter removed from synapse

Question 28

acetylcholine

Answer 28

muscle contraction neurotransmitter between neurons & muscles

Question 29

acetylcholineterase

Answer 29

enzyme that breaks down acetylcholine into acetyl & choline

Question 30

what happens after acetylecholinterase breaks down acetylcholine

Answer 30

choline is reabsorbed by presynaptic neuron to make more acetylcholine