Action Potential

Question 1

Blocks fast Na+ channels

Answer 1

Ca2+

Question 2

Ion needed for repolarization

Answer 2

K+

Question 3

Magnitude of end plate potential is related to..

Answer 3

Amount of acetylcholine released

Question 4

Receptor for acetylchoine

Answer 4

Nicotinic receptor

Question 5

Which neurons release Ach

Answer 5

parasympathetic pre and postganglionic fibers

Question 6

Which receptors norepinephrine binds to?

Answer 6

alpha and beta 1/3 receptors, which are G-coupled proteins

Question 7

Isometric contraction

Answer 7

Force is not sufficient to move the load, muscle doesn’t shorten

Question 8

Isotonic contraction

Answer 8

Force is sufficient to move the load, muscle shortens

Question 9

Two ways force in skeletal muscle can be increased

Answer 9

Summation and recruitment

Question 10

Removal of Ca2+ in cardiac myocytes

Answer 10

SERCA and Na+-Ca2+ exchanger

Question 11

Dominates when cytosolic calcium is high

Answer 11

Myosin Light Chain Kinase

Question 12

Motor Unit

Answer 12

Lower motor neuron plus muscle it innervates

Question 13

Type of muscle that had many fibers per motor unit

Answer 13

Antigravity muscle eg. back muscle

Question 14

Determines effect of neurotransmitter on post-synaptic membrane

Answer 14

The type of membrane and the channels presents

Question 15

Which channels cause depolarization and which channels are inhibitory?

Answer 15

Na+ channels cause depolarization, Cl- channels are inhibitory

Question 16

Myotatic/ Ia/ Muscle stretch reflex

Answer 16

muscles are made of extrafusal fibers with parallel intrafusal fibers (dilated middle)

They tell the motor system about the motor system

Question 17

Myotatic reflex

Answer 17

Autogenic reflex
Synergistic reflex
reciprocal inhibition
Renshoir inhibition

Question 18

Reverse myotatic reflex/ Ib reflex

Answer 18

Regulates tension the muscle produces