Zoology - Digestion and Absorption Question with Solution | TestHub

In histology of alimentary canal, the muscularis externa is much thicker because the faeces are large and heavy and require more force to push along. The outer longitudinal layer of the colon thins out into 3 discontinuous longitudinal bands, known as taeniae coli (bands of the colon). Muscularis is formed by smooth muscles usually arranged into an inner circular layer and outer longitudinal layer.