Question

multiple choice question
the sarcolemma penetrates deep into the muscle fiber by forming a

sarcoplasmic reticulum
thick filaments
mitochondria
transverse (t) tubule

Explanation:

The sarcolemma forms transverse (T) tubules to penetrate deep into the muscle fiber. The sarcoplasmic reticulum is involved in calcium - ion storage. Thick filaments are part of the sarcomere. Mitochondria are the power - houses of the cell.

Answer:

D. transverse (T) tubule