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 bio-chemistry digestion of food types of ecological pyramids the muscular system and digestive system in human beings introduction to human digestive system

The fluid secreted in the mouth for partial breakdown of food is called as

  1. Gastric juice

  2. Pancreatic juice

  3. Saliva

  4. Hormone
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Saliva is present in the buccal cavity. It helps in lubricating and adhering the masticated food particles into a bolus.(mass of food) has salivary amylase that hydrolyzed 30% of starch into maltose. Hence, it helps in particle digestion of food.

So the correct answer is 'Saliva'.

Multiple choice bio-chemistry digestion of food types of ecological pyramids the muscular system and digestive system in human beings introduction to human digestive system

A bolus is

  1. A mass of crushed food moistened with saliva

  2. The semisolid material resulting from partial digestion in the stomach

  3. The milky emulsified fat absorbed from small intestine

  4. Indigestible materials that help in movement and absorption of food
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A bolus is a mass of crushed food moistened with saliva.

So the correct option is A.

Multiple choice innate and learned behaviour option a: neurobiology and behaviour biology

Alcohol is

  1. Appetiser

  2. Gastric irritant

  3. Stimulates gastric secretions

  4. Speeds up digestion
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Alcohol is a gastric irritant because it can cause many problems in gastrointestinal tract. Drinking alcohol can trigger production of more acid in the stomach which can cause burning sensation. It can also cause gastritis in which inflammation of lining of stomach occurs. Ulcers, the open sores in stomach lining can also occur due to acid in stomach. Drinking too much alcohol can cause reflux of acidic gastric juices in the oesophagus which cause a burning sensation and this condition is called heartburn. 
So, the correct answer is 'Gastric irritant'.
Multiple choice innate and learned behaviour option a: neurobiology and behaviour biology

In alcoholics, liver gets damaged due to

  1. Accumulation of fats

  2. Storage of glycogen

  3. Secretion of more bile

  4. Detoxification of alcohol
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Consuming alcohol cause fatty liver syndrome. It is the build-up of fat in liver. Gradually the liver hardens and dries up. The healthy cells of liver are replaced by fibrous tissue. This leads to build up of scar tissue in liver and leads to cirrhosis. Due to this, activities like protein synthesis and glycolysis are greatly reduced in liver. The structure of liver also gets changed and blood flow is blocked. Ultimately, it leads to failure of liver.
So, the correct answer is 'Accumulation of fats'.
Multiple choice

Where are degradable proteins broken down?

  1. Rumen

  2. Reticulum

  3. Omasum

  4. Abomasum
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Degradable intake protein (DIP) is broken down by the microbial population residing in the rumen. This microbial fermentation allows the cow to utilize nitrogen sources for protein synthesis.

Multiple choice bio-chemistry food through digestive tract absorption of food absorption parts of the digestive system: structure and function

Food  is largely absorbed in 

  1. Stomach

  2. Oesophagus

  3. Small intestine

  4. Colon
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Stomach - It is a hotbed of digestive activity, but virtually nothing (except alcohol) is absorbed there. 
Oesophagus - Nothing is absorbed in the oesophagus.  The esophagus is a tube that connects the throat and the stomach. If the mouth is the gateway to the body, then the esophagus is a highway for food and drink to travel along to make it to the stomach. 

Small Intestine - It is the site of virtually all nutrient absorption, including proteins, carbohydrates, fats and water, as well as vitamins and minerals.

Colon - It extracts water and salt from solid wastes before they are eliminated from the body and is the site in which flora-aided (largely bacterial) fermentation of unabsorbed material occurs. Unlike the small intestine, the colon does not play a major role in absorption of foods and nutrients.
So. the correct option is 'Stomach'.
Multiple choice bio-chemistry food through digestive tract absorption of food absorption parts of the digestive system: structure and function

In which of the following parts of the alimentary canal does absorption of nutrients and drugs takes place?

  1. Mouth

  2. Stomach

  3. Small intestine

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Absorption of nutrients and drugs is mainly carried out by the small intestine but the stomach also absorbs certain drugs, water, and alcohol while mouth absorbs a very little amount of water and drugs and breaks down starch.

So the correct option is 'All of the above'.

Multiple choice bio-chemistry food through digestive tract absorption of food absorption parts of the digestive system: structure and function

State which of the following statement is true OR false.
(A) No absorption of food takes place in mouth and oesophagus.
(B) Absorption of glucose depends on sodium ion.
(C) Whole protein particles can be engulfed by pinocytosis.

  1. B and C are true, A false

  2. All are true

  3. A and C are true, B is false

  4. A and B true, C false
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

  • After food is being swallowed, from the mouth it is transported to the stomach. No absorption of nutrients takes place in the mouth and oesophagus. Hence, No absorption of food takes place in the mouth and oesophagus.
  • Active glucose absorption is thought to depend on a gradient of sodium ion concentration across the brush border membrane of intestinal epithelial cells. Specifically, glucose absorption was minimally reduced when intraluminal sodium concentration was reduced. Hence, Absorption of glucose depends on sodium ion.
  • Pinocytosis is the absorption of liquids, whereas phagocytosis is the absorption of solid objects which are essentially food for the cell. Phagocytosis engulfs whole particles, which are later broken down by enzymes, such as cathepsins, and absorbed into the cells. Hence, Whole protein particles cannot be engulfed by pinocytosis.
So, the correct answer is 'A and B true, C false'.

Multiple choice bio-chemistry food through digestive tract absorption of food absorption parts of the digestive system: structure and function

What is correct about microvilli?

  1. Also known as brush bordered epithelia

  2. Found in small intestine and PCT both

  3. Increase absorption of food

  4. These are infoldings of cell membrane
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  1. Brush bordered epithelium is microvilli covered Epithelial surface found in the body.
    2. The columnar and cuboidal epithelium of small intestine and PCT have the surface covered with microvilli for increasing absorption.
    3. Cilia are meant for the movement of fluid while microvilli function to increase the absorption and secretion.
    4. Microvilli are microscopic cellular membrane protrusions that increase the surface area for diffusion and are involved in a wide variety of functions, including absorption, secretion, cellular adhesion, and mechanotransduction.
    So, the correct option is 'Increase absorption of food.
Multiple choice bio-chemistry food through digestive tract absorption of food absorption parts of the digestive system: structure and function

Choose the correct answers from the alternatives given.
The villi present on the wall of the small intestine

  1. secrete digestive enzymes

  2. increase the surface area for absorption

  3. hold mucus, so ulcers do not form

  4. hold products of digestion, so they do not enter the large intestine
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

 The absorption of digested carbohydrates, proteins and fats  is done in the small intestine with the help of villi which helps increase the surface area of the intestine. Villi are finger like projections on the intestinal wall that absorbs digested food material. Carbohydrates and proteins are absorbed into blood, while fats are absorbed into the lymph

So, the correct answer is 'increase the surface area for absorption'