Muscle physiology

Question 1

What is the name of the thin contractile protein?

Answer 1

Actin

Question 2

What is the sarcoplasmic recticulum?

Answer 2

(net-like) labyrinth of tubules inside fiber

Question 3

What do the T-tubules do?

Answer 3

connect sarcoplasmic reticulum with outer membrane (sarcolemma)

Question 4

What is connective tissue?

Answer 4

comprised of collagen

Surrounds myofibrils, muscle fibers and muscle bundles

continuous with and part of the tendon.

Question 5

What is difference between muscle and tendon?

Answer 5

Muscles_ are attached to the bones to create movement.

Tendons are the strong fibrous tissues that attach muscle to bone.

Question 6

What does a neural impulse do?

Answer 6

Makes a muscle contract

Question 7

Briefly describe how impulse makes muscle contract

Answer 7

• impulse crosses synapses and gaps using acetylcholine
• impulse arrives at motor end plate
• Impulse travels over sarcolemma and t-tubules causing calcium to be released
• release of calcium causes cross bridging of actin and myosin

Question 8

Slow twitch vs fast twitch

Answer 8

Slow twitch: contract slowly but dont fatigue quick
Less powerful
Suited for _repeated contractions
Fast twitch: contract quickly but fatigue quickly
powerful
greater force and speed

Question 9

How long does it take for both slow and fast twitch to rach peak and how many muscle fibers used?

Answer 9

Slow twitch: 110 milleseconds, 100 muscle fibers

Fast twitch: 50 milleseconds, 500 muscle fibers

Question 10

What are some training affect on muscle fiber type?

Answer 10

• Increased capillarization and aerobic capacity (more efficient slow twitch)
• Increased motor unit activation of the desired muscle fibres