The contractile units of skeletal muscles are_________ .
A) myofibrils
B) mitochondria
C) microtubules
D) T tubules

Question

Quizplus · Accepted Answer

Myofibrils are the contractile units of skeletal muscles, composed of repeating units called sarcomeres. Mitochondria are responsible for producing ATP for muscle contractions, but they are not the contractile units themselves. Microtubules are part of the cytoskeleton and are involved in intracellular transport, but they are not directly involved in muscle contraction. T tubules are invaginations of the plasma membrane and are involved in transmitting signals from the neuromuscular junction to the sarcoplasmic reticulum, but they are not the contractile units themselves.

The Contractile Units of Skeletal Muscles Are_________