Physiology- Muscular

Question 1

What is the contractile until of muscle?

Answer 1

sarcomere

Question 2

What is the name of the organelle in the muscle cell that is high in calcium?

Answer 2

sarcoplasmic reticulum

Question 3

What is the neurotransmitter of the neuromuscular junction?

Answer 3

acetylcholine

Question 4

What substance fluxes through open gated channels when the action potential reaches the terminal bouton?

Answer 4

calcium

Question 5

The depolarization of the post-synaptic membrane is known as what?

Answer 5

The end plate potential

Question 6

Why will the end plate potential always reach threshold every time?

Answer 6

because it is a suprathreshold

Question 7

What stops the action of acetylcholine in the synaptic cleft?

Answer 7

acetyl choline esterase

Question 8

Adrenergic synapses use what neurotransmitter?

Answer 8

norepinephrine

Question 9

What are the 2 contractile proteins of muscle?

Answer 9

Actin and myosin

Question 10

Which of the contractile proteins is found in the thin filament?

Answer 10

actin

Question 11

Which of the contractile proteins is found in the thick filament?

Answer 11

myosin

Question 12

What are the 2 regulatory proteins that are also found on the thin filament?

Answer 12

troponin, tropomyosin

Question 13

Which is the regulatory protein that has an inhibitory action on the formation of actin-myosin complex?

Answer 13

tropomyosin

Question 14

What substance causes the troponin-tropomyosin complex to fall away from the active site of the actin molecule?

Answer 14

calcium

Question 15

to which of the regulatory proteins does calcium bind?

Answer 15

troponin

Question 16

What substance is bound to the myosin head?

Answer 16

ATP

Question 17

What two things do we need to get the muscle to relax?

Answer 17

1. Removal of calcium

2. ATP bound to the myosin head

Question 18

Lifting and setting down contraction with muscle shortening and lengthening is known as what type of contraction?

Answer 18

Isotonic

Question 19

Contraction with no external muscle shortening is what type of contraction?

Answer 19

Isometric

Question 20

The force-velocity curve depicts what type of muscle contraction?

Answer 20

isotonic (velocity indicates movement)

Question 21

The length-tension curve depicts what type of muscle contraction?

Answer 21

Isometric

Question 22

Posture, heat generation, nerve nutrition of muscle and general circulation are all function of what?

Answer 22

muscle tone

Question 23

What is it called when a series of action potentials reach a muscle such that it cannot relax and so force within a muscle is built to a maximum?

Answer 23

summation of twitches –> tetany

Question 24

Accumulation of calcium in the cytoplasm is the mechanism for what?

Answer 24

summation of twitches

Question 25

What are the 3 muscle types?

Answer 25

Fast oxidative glycolytic Slow oxidative Fast glycolytic

Question 26

Marathon runners have more of what muscle fiber?

Answer 26

slow oxidative

Question 27

Sprinter have more of what type of muscle fiber?

Answer 27

fast glycolytic

Question 28

Where do you find smooth muscle in the body?

Answer 28

Hollow organs, blood vessels, lymphatics, skin (piloerection), eye

Question 29

What are the 2 different types of smooth muscle?

Answer 29

1. Multi unit | 2. visceral-contracts as a single unit

Question 30

Piloerection and the ciliary muscles of the eyes are examples of what type of muscle?

Answer 30

multi unit smooth muscle

Question 31

Gap junctions are found in which type of smooth muscle?

Answer 31

viscera (single unit)

Question 32

What is the cytoplasmic binding protein found in smooth muscle?

Answer 32

Calmodulin

Question 33

What are 2 possible sources of calcium for smooth muscle contraction?

Answer 33

1. mitochonrion | 2. intracellular vescicles

Question 34

How does relaxation of smooth muscle differ from relaxation of skeletal muscle?

Answer 34

It requires a light chain phosphates enzyme to remove phosphate from myosin. In skeletal muscle, relaxation is based on the repute of calcium and ATP binding to myosin head

Question 35

What are the 2 types of action potentials in smooth muscle?

Answer 35

1. spike potential | 2. Plateau potential

Question 36

The gut, blood vessels experience what type of smooth muscle action potential?

Answer 36

spike

Question 37

The uterus and bladder experience what type of smooth muscle action potential?

Answer 37

plateau potential

Question 38

Smooth muscle contraction is regulated in what 2 ways?

Answer 38

1. Neurally i.e. via neurotransmitters | 2. hormonally via blood borne agents (epic), local tissue factors (O2, CO2, H+)

Question 39

What happens to smooth muscle when it is stretched?

Answer 39

It will often lead to a spike potential and a contraction