The "knee jerk" or stretch reflex is due to the activation of the
A) Golgi tendon organ
B) muscle spindle

Question

Quizplus · Accepted Answer

The knee jerk reflex, also known as the patellar reflex, is a monosynaptic reflex arc that is initiated by the activation of the muscle spindle in the quadriceps muscle. When the patellar tendon is tapped, the stretch of the quadriceps muscle stretch triggers an afferent impulse that activates the muscle spindle, which in turn stimulates the alpha motor neuron to contract the muscle and initiate the knee jerk reflex. The Golgi tendon organ is another type of sensory receptor found in muscles but it is involved in the inverse myotatic reflex (reflexive muscle relaxation in response to excessive tension in the muscle), not the knee jerk reflex.

The "Knee Jerk" or Stretch Reflex Is Due to the Activation