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it contains many villi that increases the surface area of absorption.
(c) It also helps in absorption of fats.
Although it is shorter but, is called large intestine, because it is wider in diameter
than small intestine.
Large intestine lacks villi and microvilli
It is distinguishable into three main parts
(a) Caecum It is a small pouch-like structure connected to the terminal part of small
intestine. It is a blind sac that functions as a host for various symbiotic
microorganisms. Vermiform appendix, a narrow finger-like projection which is a
vestigial organ arises from caecum.
Both the structures are not well-developed in human beings, but in herbivores it is
developed very well in order to digest cellulose whose digestion is difficult.
finally opens into large intestine on the right side of the abdominal cavity.
(b) Colon It is the longest part of the large intestine. The caecum opens into colon,
which is further divisible into three main parts, i.e., an ascending colon, transverse
colon and descending colon.
(c) Rectum It is the last part of the large intestine. The descending colon finally
opens into rectum, which serves to store the faecal matter temporarily. It further
leads to a short anal canal, which opens to outside through anus.
The anal canal is guarded by another sphincter, i.e., internal and external sphincter,.
At the ileocaecal junction is an ileocaecal value is present, that regulates the
passage of materials from small to the large intestines.

Digestive Glands
To bring about the chemical simplification of food, digestive juices are secreted by
the different glands. The digestive glands associated with the alimentary canal
include majorly salivary glands, the liver and pancreas.
i. Salivary Glands
These are exocrine glands that secretes saliva. There are three pairs of salivary
glands in man. All three glands are situated just outside the buccal cavity and
secrete salivary juice into the buccal cavity. These are as follows:
(a) Parotid Glands These are largest of the three glands present one on either side of
the cheek on the upper palate.
(b) Sub-maxillary or Sub-mandibular Glands These are present at the angle of the