Observe the figure given below and answer the following questions- (i) What does the figure represent? (ii) Label the parts 1-3 (iii) Mention the role of structure shown in the figure.

The figure represents the villi. The complete digestion and absorption of food takes place in the small intestine. The finger-like projections found on the inner wall of the small intestine are richly supplied with blood vessels. These structures are called villi. These structures increase the surface area for the absorption of food. The diagram of the villi of the small intestine. The villi are finger-like projections that increase the surface area for the absorption of digested food. The food diffuses through the epithelium into the blood vessels. Glucose, amino acids, minerals, and vitamins are absorbed by the branches of the hepatic portal vein, which take the food to the liver. The fatty acids and the glycerol are absorbed by the lacteal, which are carried in the lymph vessels to the point where the lymph vessels empty into the blood stream.

Observe the figure given below and answer the following questions- (i) What does the figure show? (ii) Label the parts marked 1-12 (iii) Mention the functions of parts 3, 4, 6, 8, and 9.

The diagram represent the human digestive system that consists of the alimentary canal and the associated digestive glands-salivary glands, the liver, and the pancreas. The labelled diagram of the human digestive system shows the mouth, oesophagus, stomach, small intestine, large intestine, and digestive glands. Part 3 is the stomach that secretes gastric juice which consists of HCl and the enzymes pepsin and rennin. HCl kills bacteria and provides an acidic medium for the digestion of proteins. Pepsin converts the proteins into peptones. Rennin hydrolyses soluble casein into paracasein and whey protein. Part 4 is the gall bladder that stores the bile secreted by the liver. The bile creates the alkaline medium for the digestion of fats and causes the emulsification of fats. Part 6 is the pancreas that secretes pancreatic juice into the small intestine for the digestion of food. The pancreatic juice consists of the following enzymes- Lipase-converts fats into fatty acids and glycerol. Amylase-converts the starch into maltose. Trypsin-converts proteins into peptones, and the peptones into peptides and amino acids. Part 8 is the small intestine that secretes the following enzymes- Erepsin-converts peptones into amino acids. Maltase-converts maltose into glucose. Lactase-converts lactose into glucose and galactose. Sucrase-converts sucrose into glucose and fructose. Lipase-converts fats into fatty acids and glycerol. The villi of the small intestine increase the surface area for the absorption of food. Part 9 is the large intestine. The undigested food move forward into the large intestine. The absorption of water takes place in the large intestine and the solid waste is removed from the body through the anus.

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A New Approach to I.C.S.E. Biology>Chapter 13 - Digestive System>Exercises

Exercises

Author:Dr. S.K. Aggarwal

Dr. S.K. Aggarwal Biology Solutions for Exercises

Simple step-by-step solutions to Exercises questions of Digestive System from A New Approach to I.C.S.E. Biology. Also get 3D topic explainers, cheat sheets, and unlimited doubts solving on EMBIBE.