The Lumen of the Transverse Tubules of Skeletal Muscles Contains

Question

The lumen of the transverse tubules of skeletal muscles contains
A) extracellular fluid.
B) cytosol.
C) actin.
D) myosin.
E) sarcomeres.

Accepted Answer

The lumen of the transverse tubules contains extracellular fluid, which helps to facilitate the rapid transmission of signals across the muscle fiber.

Answer: B 
 The cytosol, or intracellular fluid, is found within the muscle fiber itself, but not in the lumen of the transverse tubules.

Answer: C 
 Actin is a major component of the thin filaments within the sarcomeres, but is not found within the lumen of the transverse tubules.

Answer: D 
 Myosin is a major component of the thick filaments within the sarcomeres, but is not found within the lumen of the transverse tubules.

Answer: E 
 Sarcomeres are the repeating units of myofibrils, and are found within the muscle fiber itself, but not in the lumen of the transverse tubules.