Which statement does NOT correctly describe the defecation reflex?
A)It is initiated when mass movements force fecal material into the rectum, stimulating stretch receptors in the rectal wall.
B)It involves relaxation of the internal anal sphincter.
C) It cannot be overridden by voluntary contraction of the external anal sphincter.
D) It involves contraction of the sigmoid colon and rectum.

Question

Quizplus · Accepted Answer

The defecation reflex can be overridden by voluntary contraction of the external anal sphincter, which allows us to control the timing of defecation.

Which Statement Does NOT Correctly Describe the Defecation Reflex