Approximately 80% of a muscle fiber's volume are the myofibrils. This characteristic reflects muscles ability to__________ .

Question

Quizplus · Accepted Answer

Myofibrils are responsible for the contractile force of muscle fibers, making choice C the correct answer. Oxygen is stored in myoglobin, not in the myofibrils, so choice A can be eliminated. While action potentials are propagated along the sarcolemma (the muscle cell membrane), myofibrils are not directly involved in this process, so choice B can be eliminated. Myofibrils do play a role in producing ATP through the breakdown of glucose during cellular respiration, however, the amount of ATP produced is not necessarily higher than in other cellular structures, so choice D can be eliminated.

Approximately 80% of a Muscle Fiber's Volume Are the Myofibrils