The job of the sigmoid colon is to solidify stool before it enters the rectum and anal canal for excretion. It does this by contracting, and the increased pressure moves the stool.

Bladder volume data was tabulated into five groups according to increasing volume of bladder. It was correlated with D2cc dose received by bladder, rectum and sigmoid colon. Results: Statistical ...

Some people have a sigmoid colon that’s a bit longer than usual, which is a normal variation in human anatomy, she adds. “I was always told I had a long colon,” Grenham recalls.