When the doctor uses a reflex hammer on your patellar ligament and you experience a "knee jerk" this is an example of a
A) polysynaptic withdrawal reflex
B) monosynaptic stretch reflex
C) monosynaptic withdrawal reflex
D) polysynaptic stretch reflex

Question

Quizplus · Accepted Answer

When the doctor uses a reflex hammer on the patellar ligament, the muscle spindle in the quadriceps muscle is stretched, which activates the sensory neuron. The sensory neuron synapses directly with a motor neuron in the spinal cord, which causes the quadriceps muscle to contract and the leg to extend, resulting in the "knee jerk" reflex. This is an example of the monosynaptic stretch reflex.

When the Doctor Uses a Reflex Hammer on Your Patellar