The contraction of a muscle involves: I. Nerve impulseII. EnergyIII. Calcium ions
Correct answer: E. I, II, & III
- A. I only
- B. ll only
- C. I & III only
- D. II & III only
- E. I, II, & III
Explanation
Muscle contraction takes place when a NERVE IMPULSE from a motor neuron reaches a neuromuscular junction.The nerve impulse travels to T-tubules where they cause sarcoplasmic reticulum to release Ca²+ ions.These ions then attach with troponin that causes them to move slightly.This movement exposes the binding sites on actin and myosin attaches to it to contract the muscle. To relax the muscle,ATP provides ENERGY to break the actin-myosin bridge and attachment site of actin is covered again. Hence, All three(Nerve impulse,Energy and Ca²+) are involved in muscle contraction. So,Option E is correct.
Last updated
About Support and Movement
Support and movement covers the axial and appendicular skeleton, bone structure, joints and the arrangement of skeletal muscles. Muscle contraction is explained through actin, myosin, sliding filaments, calcium ions and ATP, while arthritis is distinguished as a disorder of joints rather than a normal part of movement.
Practise Support and Movement
738 free Support and Movement MCQs from Biology, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Biology questions like this
Biology is on 6 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.