Which among the following is the contractile unit of muscle?
The basic contractile unit of skeletal muscle is the sarcomere. Sarcomeres are connected to each other by their Z lines. Each sarcomere contains an array of filaments that consist of actin and myosin molecules, which interact to produce contractile force. Ref: Medical Physiology: Principles for Clinical Medicine By Rodney A. Rhoades, Ph.D., David R. Bell, Ph.D., 2012, Page 141; Guyton's physiology 22nd edition, Page 73.
Sarcomere
Sarcolemma
Myofibril
Sarcotubular System