Julia has just started a weight-lifting program. As she lifts a dumbbell, her muscles contract.
Explain and elucidate how muscle contraction works at the molecular level:
Explain how do actin and myosin interact in the sarcomere to bring about muscle contraction?
What roles do ATP and calcium play?
Explain the longer-term effect of Julia's program. Explain how will her muscles adapt over time to the change in workload?
Describe what happens to bones as a result of these weight-bearing exercises. Comprise a description of calcium and bone remodeling and how this associates to homeostasis.