B2 - Muscle placement

Question 1

What is actin?

Answer 1

• a protein filament

Question 2

What is myosin?

Answer 2

• thick protein filament

Question 3

What is the beginning of a muscle contraction?

Answer 3

• an impulse is sent from the brain known as ‘action potential’
• when action potential reaches the muscle, it stimulates a reaction in each sarcomere of that muscle
• receiving this action potential stimulates the ‘myosin head’ to reach out and attach to the actin

Question 4

What is calcium’s role in muscle contraction?

Answer 4

• calcium allows the myosin and actin to bind together
• in order for the process to work, there must be calcium in the sarcomere, and ATP (energy)

Question 5

What are skeletal muscles used for?

Answer 5

• not only provide movement, strength and power, responsible for …
• maintaining posture
• generating heat to maintain normal body temperature