(1.30)
To see the rest of the large intestine we'll again take the jejuno-ileum out of the picture.
The colon has four named parts: ascending, transverse, descending and sigmoid.
Before we look at these let's look at the features of the colon that make it different from the small intestine. Here's a typical length of colon. In the colon the longitudinal muscle isn't continuous: it's gathered into three strips called the teniae coli, here's one of them, here's another.
The tenia are effectively shorter than the rest of the wall of the colon, they have the effect of drawstrings, producing these bulging sacculations. In many adults these diverticuli develop over time. They're protrusions of mucosa though the muscular layer.
Here's the colon on the inside. In between the outward bulges, which are called haustra, these impressive mucosal folds can divide the lumen into separate compartments when the muscle contracts strongly. Seen in close up, the mucous membrane of the colon is smooth: there are no villi. Here's the opening to that diverticulum.
Now we'll return to the dissection, to follow the course of the colon.