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Which of the statements about the mechan...

Which of the statements about the mechanism of muscle contraction are corrcet
(I) Acetylcholine is released when the neural signal raches the motor end plate
(II) Muscle contration is initiated by a singnal sent by CNS via a sensory neuron
(III) During muscle contration, isotropic band gets elongated
(IV) Repeated activation of the muscles can be lead to lactic acid eccumulation

A

I and IV are correct

B

I and III are correct

C

II and III are correct

D

I, II and III are correct

Text Solution

Verified by Experts

The correct Answer is:
A
* Acetylcholine is released from synaptic vesicle of pre – synaptic membrane bind to the receptor present on post – synaptic membrane.
* Muscle contraction is initiated by a signal sent by CNS via a motor neuron.
* During muscle contraction isotropic band get shorten.
* Repeated activation of muscle resulted in continuous depolarisaton of muscle fibre lead to lactic acid accumulation due to anaerobic respiration.
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Which of the following statements about the mechanism of muscle contraction are correct ? (i) Acetylcholine is released when the neural signal reaches the motor end plate. Muscle contraction is initiated by a signal sent by CNS via sensory neuron. (iii) During muscle contraction, isotropic band gets elongated (iv) Repeated activation of the muscles can lead to lactic acid accumulation.

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