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

The anion present in pancreatic juice is

  1. chloride

  2. bromide

  3. phosphate

  4. bicarbonate
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Pancreatic juice contains high concentrations of bicarbonate ions (HCO3-) which neutralize the acidic chyme entering from the stomach. This creates the optimal alkaline pH needed for pancreatic enzymes to function properly in digestion.

Multiple choice

The goblet cells present in the intestinal lining are

  1. holocrine

  2. merocrine

  3. apocrine

  4. endocrine
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Goblet cells are merocrine glands because they secrete mucus through exocytosis without losing any cellular material. Merocrine secretion is the most common type, where secretory vesicles fuse with the plasma membrane and release their contents. Holocrine glands lose entire cells, apocrine glands lose portions of the cytoplasm.

Multiple choice

A chemical process common in the digestion of all kinds of food is

  1. Condensation

  2. hydrolysis

  3. phosphorylation

  4. emulsification
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Hydrolysis is the universal chemical process in digestion, where water molecules are used to break down complex molecules (proteins, carbohydrates, fats) into simpler units. Condensation is the opposite process (building up), phosphorylation adds phosphate groups, and emulsification is specific to fat breakdown.

Multiple choice

Duodenum is situated

  1. at the uppermost part of the small intestine

  2. near the lungs

  3. in the brain

  4. at the tail end of the intestine
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The duodenum is the first and shortest section of the small intestine, located immediately after the stomach. It is indeed situated at the uppermost part of the small intestine and plays a crucial role in digestion by receiving bile from the liver and digestive enzymes from the pancreas.

Multiple choice

Protein digestive enzymes of frog are

  1. trypsin, erepsin, pepsin

  2. amylose, lipase, zymase

  3. amylopsin, steapsin, ptyalin

  4. urease, steapsin, ptyalin
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Frogs are carnivorous and require protein-digesting enzymes. Trypsin and pepsin are proteases that break down proteins, while erepsin (peptidase) further breaks down peptides. Option A lists three protein-digesting enzymes. Option C contains carbohydrate enzymes (amylopsin, ptyalin) and lipase (fat), option B has incorrect combinations, and option D includes enzymes not typically found in frogs.

Multiple choice

Glycogen is stored in

  1. liver

  2. muscles

  3. liver and muscles

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

Glycogen is the storage form of glucose in animals. It is primarily stored in the liver and muscle tissues, where it can be quickly mobilized when blood glucose levels drop.

Multiple choice

Which is not a component of the digestive system of the human body?

  1. Pancreas

  2. Lungs

  3. Gall bladder

  4. Heart
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The digestive system includes organs like the pancreas, gall bladder, stomach, intestines, and liver that process food. The heart is part of the circulatory system, pumping blood throughout the body. The lungs (not listed as correct answer) are part of the respiratory system.

Multiple choice

Lac is a product of

  1. faecal matter

  2. secretion from the body

  3. excretion from the body

  4. excess food oozing out of the body

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

Lac is a resinous secretion produced by the lac insect (Kerria lacca) on host tree branches. The female insect secretes it to create a protective covering. It's not excretion, waste matter, or excess food - it's an intentional secretion harvested for shellac, dye, and other products.