Structural and functional unit of contractile apparatus in striated muscle is called

Options

(a) cross bridge
(b) myofibril
(c) Z-band
(d) sarcomere

Correct Answer:

sarcomere

Explanation:

Sarcomere is the functional unit of myofibril. It is the part of myofibril between two successive Z-lines, which consists of two I-band halves, and an A-band between them. The region contains a bundle of two types of protein filaments, actin and myosin. Upon contraction, the actin filaments slide towards the centre of the myosin filaments, and overall sarcomere length get smaller.