Muscle contraction is initiated by a signal sent by the central nervous system by the release of .
- cyclic adenosine monophosphate
- acetylcholine
- acetyl coenzyme A
- cyclic guanosine monophosphate
Answer
(2) acetylcholine
Solution
As per NCERT, muscle contraction is initiated by a signal sent by the CNS via a motor neuron. A neural signal reaching the neuromuscular junction releases the neurotransmitter acetylcholine, which generates an action potential in the sarcolemma; this spreads through the muscle fibre and causes the release of Ca2+ into the sarcoplasm, leading to contraction.
Answer: (2)