Question 1

How are fats digested in our bodies? Where does this process take place?

Accepted Answer

Answer:Fat digestion takes place in the small intestine. The alkaline secretion of the liver, bile, is carried to the small intestine by the bile duct. The process starts with emulsification (break down) of large fat globules by the salt of bile into smaller micelles to facilitate further enzymatic reaction and digestion process. The fat-digesting lipase enzyme in pancreatic juice and intestinal juices digest the fat in micelles into triacylglycerols and then fatty acids and glycerol. These fat digestion products are then absorbed by the intestinal mucosa and are carried to tissues by the lymphatic system and blood where they either serve as energy fuel or are stored after re-esterification.

Question 2

Bile juice contains no digestive enzymes, yet it is important for digestion. Why?

Accepted Answer

Bile is a digestive juice secreted by the liver. Although it does not contain any digestive enzymes, it plays an important role in the digestion of fats. Bile juice has bile salts such as bilirubin and biliverdin. These break down large fat globules into smaller globules so that the pancreatic enzymes can easily act on them. This process is known as emulsification of fats. Bile juice also makes the medium alkaline and activates lipase.

Question 3

How is small intestine designed to absorb digested food?

Accepted Answer

correct answer is option D.The small intestine is the most important part of the alimentary canal for digestion and absorption of food. It has three regions a U-shaped duodenum, a long coiled middle portion jejunum and highly coiled ileum.The innermost layer lining the lumen of the alimentary canal is the mucosa. This layer forms irregular folds (rugae) in the stomach and small finger-like foldings called villi in the small intestine. These modifications increase the surface area for more absorption. Villi are supplied with a network of capillaries and a large lymph vessel called the lacteal.It transports lipid molecules. The wall of the intestine is surrounded by the blood vessels which assimilates the food molecules to the different parts of the body.

Question 4

Choose the correct answer among the following:

(a) Gastric juice contains

(i) pepsin, lipase, and rennin
(ii) trypsin, lipase, and rennin
(iii) trypsin, pepsin, and lipase
(iv) trypsin, pepsin, and renin

(b) Succus entericus is the name given to

(i) a junction between the ileum and large intestine
(ii) intestinal juice
(iii) swelling in the neck
(iv) appendix

Accepted Answer

Gastric juice contains pepsin, lipase, and rennin. Pepsin is secreted in an inactive form as pepsinogen, which is activated by HCl. Pepsin digests proteins into peptones. Lipase breaks down fats into fatty acids. Rennin is a photolytic enzyme present in the gastric juice. It helps in the coagulation of milk.Intestinal juice :Succus entericus is another name for intestinal juice. It is secreted by the intestinal gland. Intestinal juice contains a variety of enzymes such as maltase, lipases, nucleosidases, dipeptidases, etc.

Question 5

Which is the largest gland in human body?

Accepted Answer

Liver is the largest gland in the human body that secretes bileSo, the correct answer is 'Liver'

Question 6

Give the dental formula of human beings.

Accepted Answer

The dental formula represents the arrangement of teeth in each half of the upper and the lower jaw. The entire formula is multiplied by two to represent the total number of teeth.The dental formula for milk teeth in humans is:Each half of the upper jaw and the lower jaw has 2 incisors, 1 canine, and 2 molars. Premolars are absent in milk teeth  hence the zero.The dental formula for permanent teeth in humans is: Each half of the upper jaw and the lower jaw has 2 incisors, 1 canine, 2 premolars, and 3 molars. An adult human has 32 permanent teeth.

Question 7

Name the correct substrates for the following enzymes.(a) Trypsin (b) Amylase (c) Pepsin (d) Lipase

Accepted Answer

The substrates for the following enzymes are(a)Trypsin - Protein (b)Amylase - starch (c) Pepsin -Protein (d) Lipase - Fat

Question 8

The most important function of villi in the small intestine is

Accepted Answer

Villi are tiny, finger-like projections from the wall of the small intestine. They line the inner surface of the small intestine. Their role is to increase the surface area within the small intestine. This will lead to the increase of the surface area of absorption as it is the main function of the small intestine.

Question 9

Which of the following is not the function of liver ?

Accepted Answer

The liver performs a variety of functions such as synthesis, storage and secretion of various substances. The functions performed by the liver are :The liver secretes bile juice.The liver plays a key role in carbohydrates metabolism, in lipid metabolism. It also helps in deamination of proteins and conversion of ammonia into urea. It is the chief organ of detoxification of toxic substances in food.It acts as a thermoregulatory organ like skeletal muscle. as it has high glucose at its disposal.It acts as a haematopoietic organ in the foetus and erythroblasts organ i.e. destruction of the red blood cells in the adults. Hence, the breakdown of cholesterol is not the function of the liver.So, the correct option is 'breakdown of cholesterol'.

Question 10

Give the dental formula of adult human beings.

Accepted Answer

The dental formula is used to represent the arrangement of the teeth in upper and the lower row. The dental formula for the adult human beings is 2123/2123. There are 2 incisors, 1 canine, 2 premolars aand 3 molars in one row. There are total 32 teeth in the adult human being

Revise with Concepts

Introduction to Digestion

Mouth

Teeth

Intermediate Knowledge of Teeth

Small Intestine

Quick Summary With Stories

Oral Cavity

Teeth - Types and Functions

Teeth

Basics of Teeth

Tongue and its functions

Small Intestine and its Functions