In response to a muscle being stretched,a muscle spindle initiates a somatic spinal reflex that causes
1)contraction of the agonist muscle.
2)relaxation of the antagonist muscle.
3)contraction of the antagonist muscle.
4)relaxation of the agonist muscle.
A)1 only
B)2 only
C)3 only
D)4 only
E)1 and 2

Question

Quizplus · Accepted Answer

When a muscle is stretched, the muscle spindle initiates a somatic spinal reflex that causes the contraction of the agonist (stretched) muscle and the relaxation of the antagonist (opposing) muscle. This is known as the stretch reflex and helps to maintain muscle tone and control joint movements. Therefore, choice 1 and 2 are both correct. Choices 3 and 4 are incorrect as they describe the opposite effects of what actually occurs in the stretch reflex.

In Response to a Muscle Being Stretched,a Muscle Spindle Initiates