Energy For Muscle Contraction

Question 1

How is the energy provided for muscle contraction?

Answer 1

Hydrolysis of ATP to ADP + Pi by ATP Hydrolase

Question 2

What is the energy from ATP hydrolysis used for?

Answer 2

• movement of the myosin head to allow actin to slide
• active uptake of calcium ions back into the sarcoplasmic reticulum

Question 3

Where does the ATP come from?

Answer 3

• resting muscle can store a small amount of ATP
• aerobic respiration slowly produces ATP
• anaerobic respiration produces a low concentration of ATP
• muscle fibres contain phosphocreatine which can be used to produce ATP rapidly by transferring a phosphate ion to ADP

Question 4

What is the advantage of using phosphocreatine to produce ATP?

Answer 4

Allows for muscle contraction to continue until respiration releases more ATP