Surgery>>>>>Colon, Rectum, and Anus
Question 2#

Which layer of muscle joins together to form the internal anal sphincter?

A. Circumferential muscle layer
B. Longitudinal muscle layer
C. Puborectalis muscle
D. Circular muscle layer

Correct Answer is A


The inner circular muscle joins to form the internal anal sphincter. The subcutaneous, superficial, and deep external sphincter surrounds it. The deep external anal sphincter is an extension of the puborectalis muscle.