chapter 3

Question 1

what is the resting membrane potential

Answer 1

-70 mV

Question 2

What does sodium potassium pump do?

Answer 2

pumps 3 sodium out and 2 potasium in (requires energy)

Question 3

Describe the absolute refractory period?

Answer 3

rising phase of the action potential, when sodium channels are open. no matter what another action potential cannot occur

Question 4

describe the relative refractory period?

Answer 4

depolarization phase, sodium potassium pump combined with natural permeability to potasssium causes a hyperdepolarization. A large AP is required

Question 5

what is saltatory conduction?

Answer 5

the action potential is propogated down the myelinated shealth jumping from node to node.

Question 6

name of cell that creates myelin

Answer 6

schwann cell

Question 7

how do aps travel from one cell to the next

Answer 7

across the synaptic cleft (chemical signal)

Question 8

what are the chemical messengers in axon terminals (presynaptic clefts) that carry signal?

Answer 8

neurotransmitters

Question 9

what are the chemical messengers in axon terminals (presynaptic clefts) that carry signal?

Answer 9

neurotransmitters

Question 10

what are the two main neurotransmitters related to exercise?

Answer 10

acetylcholine and norepinephrine

Question 11

what is the job of a neurotransmitter?

Answer 11

carry action potentials across synaptic cleft, trigger a graded potential in post-synaptic cleft

Question 12

significance of the neuromuscular junction?

Answer 12

its a special synpase of communcation from neuron to muscle where acetlycholine is the neurotransmitter

Question 13

Role of the primary motor cortex?

Answer 13

controls movement

Question 14

Role of the premotor cortex?

Answer 14

stores learned skills “muscle memory”

Question 15

Role of the basal ganglia?

Answer 15

initiatess sustained or repetitive movement

Question 16

what are the two parts of the diecephalon

Answer 16

thalamus and hypothalamus

Question 17

Role of the thalamus?

Answer 17

determines what we are consciously aware of

Question 18

Role of the hypothalamus?

Answer 18

homeostasis (apetite, sleep, thirst)

Question 19

Role of the cerebellum?

Answer 19

smoothes out movement

Question 20

Role of the brainstem?

Answer 20

communicates info from brain to spinal cord

Question 21

Role of the reticular formation?

Answer 21

its a nerve pathway in the brain that coordinates muscle function and tone. also controls cardio and respiratory function

Question 22

Role of the analgesia system?

Answer 22

control pain (opoids)

Question 23

significance of the spinal cord?

Answer 23

ascending and descending pathways that conduct impulses. begins at medulla oblongata

Question 24

what are the two main divisions of the PNS

Answer 24

sensory (toward) motor (away)

Question 25

what are the five types of sensory receptors?

Answer 25

chemo, thermo, nocio, mechanical, photo

Question 26

what are the two main divisions of the motor nerves?

Answer 26

autonomic: non-conscious behavior. somatic (muscle activity)

Question 27

what are the two main divisions of the somatic system?

Answer 27

parasympathetic: rest and digest. sympathetic: fight of flight

Question 28

what is a motor reflex?

Answer 28

instant, programmed response that is identical each time it happens

Question 29

What do the golgi tendon organs monitor?

Answer 29

tension, which can be created by contraction or outside force

Question 30

what do the muscle spindles monitor?

Answer 30

muscle length and change in length

Question 31

what happens if muscle spindles detect excessive length change?

Answer 31

trigger a muscle contraction

Question 32

what happens if GTO detect tension?

Answer 32

inhibit the muscle, preventing anymore tension

Question 33

what is the size principle?

Answer 33

smaller motor units will be recruited before larger ones