Join thousands of students who trust us to help them ace their exams!
Multiple Choice
What is a power stroke during muscle contraction?
A
The movement of myosin heads pulling actin filaments towards the center of the sarcomere
B
The detachment of myosin heads from actin filaments
C
The release of calcium ions from the sarcoplasmic reticulum
D
The binding of ATP to myosin heads
0 Comments
Verified step by step guidance
1
Understand the context of muscle contraction: Muscle contraction involves the interaction between actin and myosin filaments within the sarcomere, the basic unit of a muscle fiber.
Identify the role of myosin heads: Myosin heads bind to actin filaments, forming cross-bridges, which are crucial for muscle contraction.
Define the power stroke: The power stroke is the process where the myosin heads pivot, pulling the actin filaments towards the center of the sarcomere, which shortens the muscle.
Recognize the sequence of events: The power stroke occurs after the myosin heads bind to actin and before they detach, which requires ATP binding to the myosin heads.
Differentiate from other processes: The power stroke is distinct from the release of calcium ions from the sarcoplasmic reticulum and the binding of ATP to myosin heads, which are separate steps in the muscle contraction cycle.