Question

The steps involved in the mechanism of muscle contraction are given below. Arrange the steps in proper sequential order and select the correct option
I. Release of calcium ions in the sarcoplasm
II. Signal sent by the $CNS$ via a motor neuron
III. Binding of calcium with a subunit of troponin on actin filaments
IV. Generation of the action potential in the sarcolemma
V. Binding of myosin head to the exposed active sites on actin to form a cross-bridge
VI. Inward pulling of ${}^{\prime }{Z}^{\prime }$ line attached to actin causing shortening of the sarcomere
VII. Pulling of the attached actin filaments towards the centre of ${}^{\prime }{A}^{\prime }$ band
VIII. Release of neurotransmitter acetylcholine and generation of the action potential in the sarcolemma

• A. $III,II,V,I,IV,VI,VII,VIII$
• B. $II,VIII,IV,I,III,V,VII,VI$
• C. $I,VIII,VI,II,V,IV,III,VII$
• D. $II,IV,V,I,III,VII,VIII,VI$

Answer 1

Answer: (B)

Correct answer is (b) $II,VIII,IV,I,III,V,VII,VI$