The knee jerk may be classified as a segmental reflex because:

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Quizplus · Accepted Answer

The knee jerk reflex is a segmental reflex because the sensory impulses that mediate it enter and leave the same segment of the spinal cord, which is the segment at the level of the knees. This segment includes the sensory neuron, interneuron, and motor neuron that make up the reflex arc. The center of the reflex arc, where the interneuron is located, lies in the gray matter of the spinal cord at this segment. This reflex does not involve impulses from the opposite side of the body, so it is not a crossed-extensor reflex. The knee jerk reflex is typically evoked by tapping the patellar tendon with a rubber hammer, but the type of stimulation used is not what determines its classification as a segmental reflex.

The Knee Jerk May Be Classified as a Segmental Reflex