The part of the muscle which shortens to create contraction is the-
-
A.
Actin
-
B.
Epimysium
-
C.
Fasciculi
-
D.
Myosin
Correct Answer:
A. Actin
Explanation:
The sarcomere is the fundamental functional unit of a muscle fiber. It contains thick filaments made of myosin and thin filaments made of actin. During a muscle contraction, these filaments slide past one another rather than changing their individual lengths. This sliding action pulls the ends of the sarcomere closer together, causing the entire unit to shorten and generate the force required for movement. While myosin and actin are the proteins responsible for this mechanism, and the epimysium and fasciculi represent larger structural layers of the muscle, it is the shortening of the sarcomere specifically that defines the contraction at the cellular level.
Click below to open Discussion & Feedback
0 Issues
Please
login to comment or Report Issues.