MUSCLE PHYSIOLOGY

PHYSIOLOGY

NEUROMUSCULAR JUNCTION TRANSMISSION

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Contractile unit of a muscle which is also the functional unit of a muscle is ____
A
sarcomere
B
motor unit
C
fascicle
D
myofibril
Explanation: 

Detailed explanation-1: -A sarcomere is the basic contractile unit of a myocyte (muscle fibre). A sarcomere is composed of two main protein filaments (thin actin and thick myosin filaments) which are the active structures responsible for muscular contraction.

Detailed explanation-2: -The sarcomere is the smallest functional unit of a skeletal muscle fiber and is a highly organized arrangement of contractile, regulatory, and structural proteins. It is the shortening of these individual sarcomeres that lead to the contraction of individual skeletal muscle fibers (and ultimately the whole muscle).

Detailed explanation-3: -To say that the sarcomere is the functional unit means that all the components needed for contraction are contained within each sarcomere. In fact, muscle is composed of millions of tiny sarcomeres, and each sarcomere shortens, thus resulting in muscular contraction.

There is 1 question to complete.