Question

Which of the following statements is not correct?

• A. An action potential is propagated along sarcolemma and down the T - tubules.
• B. The tiny gap between the innervating neuron and the sarcolemma of the muscle fiber it is innervating, is called the T - tubule
• C. Triads in skeletal muscle consist of 2 T-tubules and a cisternae
• D. Acetylcholine at the neuromuscular junction is broken down by acetylcholinesterase, and this terminates the stream of action potentials along the muscle fiber surface.

Answer 1

The correct option is B

The tiny gap between the innervating neuron and the sarcolemma of the muscle fiber it is innervating, is called the T - tubule

Transverse tubules (T-tubules) are extensions of the sarcolemma (muscle cell membrane) that penetrate into the centre of skeletal and cardiac muscle cells.
The tiny gap between the innervating neuron and the sarcolemma of the muscle fibre it is innervating is called the synaptic cleft.