Muscle Physiology: Contraction Mechanisms · Zoology

Which molecule provides a rapid, short-term reserve of high-energy phosphates to regenerate ATP during the first few seconds of muscle activity?

  1. Lactic acid (anaerobic byproduct)
  2. Creatine phosphate
  3. Blood glucose (from circulation)
  4. Myoglobin (oxygen-storage protein)
Show answer and explanation

Correct answer: Creatine phosphate

Creatine phosphate can quickly transfer its phosphate group to ADP to form ATP via the enzyme creatine kinase. This provides enough energy for about 10–15 seconds of maximal exertion.

Difficulty: Medium Question 17 of 20

Practice all 20 Muscle Physiology: Contraction Mechanisms questions

Keep practicing

More Muscle Physiology: Contraction Mechanisms questions