Muscle Physiology

Question 1

Types of muscle
[3]

Answer 1

Skeletal
Cardiac
Smooth

Question 2

Function of skeletal muscle

Answer 2

Voluntary control
Helps to move + breathe

Question 3

Function of cardiac muscle

Answer 3

The heart

Question 4

Function of smooth muscle

Answer 4

Surround hollow organs

Question 5

How is contraction initiated

Answer 5

A rise in intracellular calcium

Question 6

In striated muscles what does calcium bind to

Answer 6

Troponin complex

Question 7

In smooth muscle what does calcium bind to

Answer 7

Calmodulin

Question 8

What is the structure of straited muscle

Answer 8

Actin and myosin forming a cross bridge

Question 9

What is a troponin complex

Answer 9

Calcium binding protein

Question 10

First step of cross bridge cycle

Answer 10

ATP binds to myosin head

Question 11

After ATP binds what happens

Answer 11

ATP is hydrolysed
Myosin head goes to resting position

Question 12

How is a power stroke created

Answer 12

When phosphate is released
Formation changes

Question 13

Cross bridge cycle
[5]

Answer 13

ATP binds to myosin head
ATP hydrolysed, myosin head goes to resting position
Cross bridge formed
P is released, making power stroke
ADP released

Question 14

How does action potential change the calcium concentration

Answer 14

AP causes ACh to release
End plate potential initiates an AP
AP cause calcium release from sarcoplasmic reticulum
Increase intracellular calcium conc cause contraction

Question 15

In skeletal muscle what is needed to cause a strongcontraction

Answer 15

Summation of twitches

Question 16

Contraction in cardiac muscle

Answer 16

AP is initiated within the sinoatrial node of the heart.
AP goes through the cardiac muscle.
Ca2+ enters each heart cell during the AP.
Ca2+ causes release of more Ca2+ from the sarcoplasmic reticulum