Question

1. Describe the major processes carried out by the digestive system.

2. Describe the general structure of the alimentary canal.

Answer 1

ANSWER - (1)

MAJOR PROCESSES CARRIED OUT BY DIGESTIVE SYSTEM : INGESTION, DIGESTION, ABSORPTION.

These are the major step happens during food consumption.

​​​​​​These 3 process starts from the mouth itself and they are leaded to the end of rectum.

in mouth saliva is secreates and attach to food and help to become bolus. Absorption of nutrients starts from mouth. Further the food is moved through esophagous and reaches stomach lumen where there Secreation of HCL (hydrochloric acid) chemical digestion takes place, Secreation of gastric juices takes place. The food is break down from macro to micro molecule, and

they are moved to the small intestine where the majority of absorption takes place. Secreations from pancrease and liver secreated to the small intestine. Pancreatic juice and bile aid in digestion of food. Special cell lining helps the nutrients and minerals to leap through the walls and reach the blood stream.

then the food is further gone to large intestine, most of the water absorption takes place here. Remaining wastes is stored as feacus and are moved to the rectum. They are later removed through anus.

ANSWER - (2)

the organs of alimentary canal have MOUTH, PHARYNX, ESOPHAGOUS, STOMACH, SMALL INTESTINE, LARGE INTESTINE.

the accessory part help in this are TEETH , TONGUE, SALIVARY GLANDS, PANCREASE, LIVER, GALL BLADDER.

TEETH helps in chewing, salivary glands helps in saliva Secreation, pancreas secreates pancreatic juice , liver secreates bile and gall bladder stores it and releases when it is needed.

ALIMENTARY CANAL :

This is continuous passage from the mouth to the anus. The Gastrointestinal tract consist of 4 layers:

1. Mucosa:

Is the inner most layer, thin layer, which have Secreations, in stomach it is gastric mucosa which contains glands and the gastric pits. Mucosa is surrounded by lumen. Mucosa is made up of three layers they are lamina propia, muscularis mucosae and the epithelium.

. 2.Sub Mucosa :

Outer layer of mucosa, this layer is composed of layer of dense, irregular connective tissue or loose connective tissue which helps in the support of mucosa. This layer consist of cappilleries , lymphatic vessels and nerves.

3: Muscularis :

consist of inner circular muscle layers, and a longitudinal outer muscle layer, This muscle layer helps in the peristaltic movement for example in esophagous. 3rd most layer which also helps in the support og mucosal and sub mucosal layer.

4. Serosa:

this is the outer most layer , this layer consist of connective tissues lining it. Simple squamous epithelium is lining it called mesothelium. Helps in the gigestive movements.