Question

If a muscle fiber were to suddenly and permanently stop producing ATP the fiber would no longer be able to actively transport calcium out of the cytoplasm (sarcoplasm) and the intracellular calcium concentration would rise. Which of the following would you expect to happen?
A) The fiber would twitch uncontrollably due to excessive calcium bound to troponin.
B) Calcium would be transported to the sarcoplasmic reticulum therefore contractions would cease.
C) Myosin would be able to bind to the exposed binding sites on thin filaments but would not be able to detach.
D) No change would occur in a muscle that was relaxed to begin with.

Answer 1

Answer:

"C" is the answer, Myosin would be able to bind to bind to the exposed binding sites on thin filaments but would not be able to detach

Explanation:

ATP is required for muscle contractions. muscle fatigue results in the decline of muscle force generated over time during metabolic fatigue there is depletion of required substrate such as ATP or glycogen as muscle is not able to generate energy to power contractions. accumulation of metabolites from this reaction other than lactic acid or reactive oxygen species can also induce fatigue by interfering with the release of Ca++ from the sarcoplasmic recticulum.