বহুনির্বাচনি (MCQ)
১. At the neuromuscular junction, release of acetylcholine is triggered by influx of:
ক) Na+
খ) K+
গ) Ca2+
ঘ) Cl-
ঙ) Mg2+
উত্তর দেখুন
সঠিক উত্তর: গ) Ca2+
ব্যাখ্যা: The action potential opens voltage-gated Ca2+ channels in the nerve terminal; Ca2+ entry makes vesicles fuse and release acetylcholine. Mg2+ and botulinum toxin reduce release.
📖 রেফারেন্স: Guyton & Hall, Textbook of Medical Physiology · Excitation of skeletal muscle: neuromuscular transmission
