) of the colon
are the small pouches caused by sacculation
, which give the colon its segmented appearance. The taenia coli
runs the length of the large intestine. Because the taenia coli is shorter than the intestine, the colon becomes sacculated between the taenia, forming the haustra. In between adjacent haustra are semi-lunar folds, known as the plicae semilunares.
Haustral contractions are slow segmenting movements that occur every 30 minutes. One haustrum distends as it fills, which stimulates muscles to contract, pushing the contents to the next haustrum.