Action potential is transmitted in myofibrils via:

Ans: B (T- Tubules) Ref: Pal GK. Muscle, In: Textbook of Medical Physiology, Ahuja Publishing House 2007: 20:177Explanation:T-Tubules are tubular extensions of sarcolemma. that penetrate to the center at the junctions of A and I bands. It is involved in conduction of action potential from NMJ to the triad formed by terminal cisternae and L tubules (part of sarcotubular system).Terminal cisternae - dilated region at both ends of elongated tubules (L-tubules), a part of Sarcoplasmic reticulum - involved in calcium release.* Sarcomere - structural functional unit of myofibril; portion of myofibril between two successive Z lines.