Biology · Science General

Human Digestive System

1,953 Questions

The human digestive system explores the breakdown of biomacromolecules, covering organs from the stomach to the small intestine. It involves physiological processes like chyme movement, pH levels, and nutrient absorption in the gut. These fundamental biology concepts are regularly featured in medical and general science competitive exams.

Small intestine functionsBiomacromolecule breakdownStomach and digestionIntestinal bacteria

Human Digestive System Questions

Multiple choice

Bile is a bitter, alkaline, brownish-yellow secreted by the liver. Which of the following statement is correct for bile?

  1. It gets diluted in the gall bladder of an individual.

  2. Hepatic bile salts act as hydrophobic molecules.

  3. Maximum bile salts are reabsorbed in the terminal ileum.

  4. Bile salts are the end products of hemoglobin present in the blood.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Most bile salts are reabsorbed in the terminal ileum and returned to the liver by the enterohepatic circulation.

Multiple choice

Which of the following statements is correct regarding the digestion and absorption by the small intestine of an individual?

  1. Intestinal digestive enzymes are secreted by cells of the oxyntic cells.

  2. Approximately 50% of the digested carbohydrate is absorbed in the small intestine.

  3. Small peptides are absorbed in the small intestine.

  4. The liver is the first organ of the digestive system to receive the digestion products of dietary fats.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is the correct answer. There is no absorption of peptide longer than four amino acids. However, there is great absorption of di- and tripeptides in the small intestine. These small peptides are absorbed into small intestinal epithelial cell by co-transport with H+ ions through a transporter called PepT1.

Multiple choice

Referring to gastro-intestinal function of an individual, which of the following events occurs in the body?

  1. The presence of enormous fat in the chyme will speed up gastric emptying.

  2. Distension of the ileum triggers gastric motility.

  3. Total gastrectomy leads to malabsorption of vitamin B12 in the body .

  4. Aldosterone restricts the absorption of sodium and water by the large intestine in the digestive system.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Intrinsic factor secreted by the parietal cells of the gastric glands is needed for the absorption of vitamin B12.

Multiple choice

Match the following:

Name of the enzymes Functions
a. Enzyme amylase 1. It breaks down the emulsified fats.
b. Enzyme trypsin 2. It digests the proteins.
c. Enzyme lipase 3. It breaks down the starch.

  1. a - 3, b - 1, c - 2

  2. a - 3, b - 2, c - 1

  3. a - 2, b - 3, c - 1

  4. a - 2, b - 1, c - 3

  5. a - 1, b - 2, c - 3
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This is the correct option. Enzyme amylase breaks down the starch. Enzyme trypsin digests the proteins. Enzyme lipase breaks down the emulsified fats.

Multiple choice

Consider the following statements:

  1. In mammals, diaphragm makes a partition between lungs and heart.
  2. A camel has three-chambered stomach.

Which of the given statements is/are incorrect?

  1. Only (1)

  2. Only (2)

  3. Both (1) and (2)

  4. Neither (1) nor (2)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Statement (1) is incorrect. In mammals, diaphragm makes a partition between thoracic and abdominal cavities. Statement (2) is correct. Yes, a camel has three-chambered stomach to store large amount of water.

Multiple choice

Which of the following statements regarding the functions of bile is/are false?

a. It makes the acidic food coming from the stomach alkaline, so that pancreatic enzymes can act on it. b. Bile salts break the fats present in the food into small globules making it easy for the enzymes to act and digest them. c. It makes the medium of gastric juices acidic, so that the enzyme pepsin can digest the proteins properly.

  1. Only a

  2. Only a and b

  3. Only b

  4. Only b and c

  5. Only c
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

This is the correct option as this statement regarding the functions of bile is false. It is the hydrochloric acid in the stomach that makes the medium of gastric juices acidic, so that the enzyme pepsin can digest the proteins properly.

Multiple choice

Match the following:

 
a. Assimilation 1. It is the process in which the food is taken into the body.
b. Ingestion 2. It is the process in which the absorbed food is taken in by the body cells and used for energy, growth and repair.
c. Digestion 3. It is the process in which the food containing large, insoluble molecules is broken down into small water soluble molecules.

  1. a - 3, b - 2, c - 1

  2. a - 2, b - 3, c - 1

  3. a - 2, b - 1, c - 3

  4. a - 1, b - 2, c - 3

  5. a - 3, b - 1, c - 2
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is the correct option. Assimilation is the process in which the absorbed food is taken in by the body cells and used for energy, growth and repair. Ingestion is the process in which the food is taken into the body. Digestion is the process in which the food containing large, insoluble molecules is broken down into small water soluble molecules.