Which of the following is true of the pectinate line of the anal canal?
A) It lies just below the level of the rectal valves.
B) It is also called the anal columns.
C) It divides regions of somatic and visceral innervation.
D) All hemorrhoids occur there.

Question

Quizplus · Accepted Answer

The pectinate line marks the transition from the upper two-thirds of the anal canal, which is derived from the hindgut and is innervated by the inferior mesenteric plexus (visceral), to the lower one-third, which is derived from the proctodeum and is innervated by somatic nerves. Therefore, it divides regions of somatic and visceral innervation.

Which of the Following Is True of the Pectinate Line