Question

multiple choice:
the main immediate source of atp (lasting about 10 seconds) as muscle contractions begin comes from:
a creatine phosphate
b glycogen
c glucose
d fat

Explanation:

Creatine phosphate can quickly donate a phosphate group to ADP to form ATP, providing an immediate source of energy for muscle contractions that lasts about 10 seconds. Glycogen, glucose, and fat are energy sources but are not the immediate source for this short - term (about 10 seconds) ATP supply at the start of muscle contractions. Glycogen needs to be broken down to glucose first, and then glucose undergoes further metabolic processes (like glycolysis). Fat is used more for long - term energy production.

Answer:

A. creatine phosphate