Muscle Tissue/Fibres [B]

Question 1

What are different parts of a muscle and what are they made of?

Answer 1

A muscle is made of a bundle of muscle fibres.
A muscle fibre is made of myofibril.
Myofibril is made of sections of sarcomeres.

Question 2

What are the 2 different proteins found in muscles?

Answer 2

Actin filament (thin)
Myosin filament (thick)

Question 3

How do muscles contract and relax?

Talk about sarcomeres and their structure

Answer 3

• Actin filaments surround myosin filaments in column.
• To contract, Myosin filaments pull on the actin filaments until they overlap.
• To relax, Actin filaments extend until they no longer overlap with myosin filaments.

Question 4

What do sarcomeres contain?

Excluding the 2 proteins

Answer 4

• Lots of mitochondria for energy
• Sacrolemma is the surrounding membrance
• Sacroplasm (like cytoplasm)
• Sarcoplastic Reticulum stores calcium ions (for contraction)

Question 5

What is the purpose/characteristics for Fast and Slow twitch muscle fibres?

Answer 5

Fast - Speed over endurance, few mitochondria and capillaries, anaerobic respiration and quick fatigue
Slow - Endurance over speed, lots of mitochondria and capillaries, aerobic respiration and slow fatigue