Biology · Science General

Human Digestive System

2,002 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

Which among the following statements is TRUE regarding the salivary secretion and swallowing in human beings?

  1. The segmentation movements propel down the bolus .

  2. The pH of saliva in the buccal cavity accelerates as its rate of secretion increases.

  3. Hormones play more significant role than nerves in the governing of salivary secretion.

  4. Swallowing in humans is a totally voluntary activity.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

As salivary secretion increases, so does its bicarbonate concentration. This results in an increase in salivary pH.

Multiple choice

Select the CORRECT statement regarding the control of gastric secretion in humans.

  1. Parietal cells of the gastric glands secrete gastric acid in response to hormonal stimulation.

  2. In an individual, most of the acid and pepsinogen released by the stomach takes place during the intestinal phase of gastric secretion.

  3. Gastric secretion does not commence unless the bolus reaches the stomach of an individual..

  4. Secretin being released by the duodenum stimulates gastric secretion in the stomach.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Parietal cells produce gastric acid, a strong acid that helps to break down food. These cells produce gastric enzymes such as pepsinogen and lipase, which helps us to digest.

Multiple choice

Which among the following statements is TRUE for gastric motility?

  1. Gastric emptying is restricted by the enterogastric reflex.

  2. The fundus region of the stomach is important for the storage of food.

  3. Contractions of the stomach wall do not begin unless the bolus enters the stomach.

  4. The contractions of the stomach depend on activity in the sciatic nerve.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The enterogastric reflex is a general term, which is used to describe all the hormonal and nervous mechanisms that control gastric emptying.

Multiple choice

Which of the following statements is correct regarding pancreatic secretion of the body?

  1. Pancreatic secretion is restricted by gastrin being secreted by the G cells of the antrum.

  2. Pancreatic acinar cells accomodate trypsin.

  3. Cholecystokinin restricts secretion from the exocrine pancreas.

  4. The commencement of acid into the duodenum stimulates pancreatic secretion.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This statement is correct.  Acid in contract with the duodenal wall causes the secretion of secretin, which stimulates a copious alkaline secretion by the cells of the pancreatic ducts.

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

Directions: The following question consists of certain statements. You have to select the option representing the most logical sequencing of the given statements.

A. Humans need energy. B. Energy is provided by food. C. Food needs to be digest. D. Enzymes help in digestion. E. Food is digested by enzymes. F. Enzymes are released in intestines.

  1. ABE

  2. BCD

  3. CDE

  4. DEF

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

As food needs to be digest and enzymes help in digestion, therefore, food is digested by enzymes. Hence, option 3 is the correct answer.