Question

Stimulation of muscle fibre by a motor neuron occurs at

• A. Transverse tubules
• B. Neuromuscular junction
• C. Myofibril
• D. Sarcoplasmic reticulum

Answer 1

The correct option is B Neuromuscular junction

• Muscle contraction is initiated by a signal sent by the central nervous system (CNS) via a motor neuron.
  
• Neuromuscular junction refers to the junction between a motor neuron and the sarcolemma of the muscle fiber.
  
• A neural signal reaching this junction releases a neurotransmitter (Acetylcholine) which stimulates the muscle fibre by generating an action potential in the sarcolemma. Hence Stimulation of muscle fiber by a motor neuron occurs at the neuromuscular junction.
  
• So, the correct answer is 'Neuromuscular junction'.