Module 6

Question 1

Whats distinguishes skeletal muscle from smooth and cardiac?

Answer 1

• multinucleated
• voluntary
• intercalated discs

Question 2

Types of troponin and what they do

Answer 2

TnI - inhibits binding of subunits to actin
TnT - binds to tropomyosin
TnC - binds calcium ions

Question 3

What anchors the sarcomere (myoribrillar array) to the cell membrane?
And also participates in the transfer of force via the help of integrins?

Answer 3

Dystrophin

Question 4

What does titin do?

Answer 4

Connects myosin to the z lines
- can participate in cell signaling

Question 5

What does Ca activate during neuromuscular junction?

Answer 5

CaM kinase 2

Question 6

What are the receptors that cause crossbridge cycle to begin?

Answer 6

Dihydropyridine receptors react to the action potential of t tubules and signal to ryanodine receptors, which release calcium for contraction to begin

Question 7

Difference btwn oxidative and glycolytic fibers

Answer 7

Oxidative:
- more oxygen, more mitochondria, red color, high myoglobin, smaller, resistant to fatigue
Glycolytic:
- low myoglobin, pale color, larger, more glycogen, less oxygen

Question 8

Cause of malignant hyperthermia

Answer 8

Uncontrolled Ca release and rise in body temp

Question 9

Cause of myesthenia gravis

Answer 9

Decrease in number of Ach receptors on the end plate

Question 10

What is not found in smooth muscle

Answer 10

Troponin or t tubules