Which effector listed below is found in the reflex arc for defecation?
A) Stretch receptors in the rectal wall
B) Spinal cord
C) The rectal wall
D) Motor neurons in the rectal wall

Question

Quizplus · Accepted Answer

Stretch receptors in the rectal wall send messages (afferent sensory neuron) to the spinal cord (integration center). The spinal cord sends motor messages (efferent motor neuron) to the rectal wall telling it to contract (effector). The spinal cord also sends messages along motor neurons to the internal anal sphincter, telling it to relax (effector).

Which Effector Listed Below Is Found in the Reflex Arc