Free Digestion MCQs with Answers
680 Digestion MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
The human digestive system covers the organs from mouth to anus, the movement of food, and the mechanical and chemical breakdown of carbohydrates, proteins and fats. It also includes the roles of digestive enzymes, bile, absorption through intestinal villi, and the assimilation of nutrients by body cells.
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- A. If only I follows
- B. If only II follows
- C. If either I or II follows
- D. If neither I nor II follows
- E. If both I and II follow
Explanation: The statement highlights a lack of access to education in tribal areas.
Correct answer: If both I and II follow- A. Increase the surface area for water absorption
- B. Shield the intestinal wall against the altering pH
- C. Assist the movement of undigested food material
- D. Facilitate the membrane proteins in ion transportation
Explanation: In the human digestive system, the large intestine plays a crucial role in absorbing water and electrolytes, forming and expelling feces.
Correct answer: Shield the intestinal wall against the altering pH583. The given flowchart shows the working of a gastrointestinal hormone.Hormone X is identified as:
- A. Renin
- B. Pepsin
- C. Gastrin
- D. Secretin
Explanation: When stomach releases acidic chyme into duodenum, duodenum produces secretin which causes pancreas to release a bicarbonate rich sectetion…
Correct answer: Secretin- A. Saliva
- B. Gastric juice
- C. Intestinal juice
- D. Pancreatic juice
Explanation: The question asks about secretions that do not contain enzymes for digesting polysaccharides and disaccharides.
Correct answer: Gastric juice- A. Eating red meat
- B. Vigorous exercises
- C. Infection by Helicobacter pylori
- D. Infection by Entamoeba histolytica
Explanation: Peptic ulcers are sores that develop on the lining of the stomach, lower esophagus, or small intestine, mainly due to an infection by the…
Correct answer: Infection by Helicobacter pylori- A. A
- B. B
- C. C
- D. D
Explanation: Parietal cells produce HCL and zymogen cells produce pepsinogen. So option C is correct and A, B, and D are incorrect as they give wrong…
Correct answer: C- A. Pyloric sphincter is relaxed
- B. Cardiac sphincter is relaxed
- C. Pyloric sphincter is contracted
- D. Cardiac sphincter is contracted
Explanation: The correct answer is that the pyloric sphincter is relaxed. In the digestive process, the pyloric sphincter plays a crucial role in…
Correct answer: Pyloric sphincter is relaxed- A. Stomach and Liver
- B. Liver and Pancreas
- C. Stomach and Pancreas
- D. Liver and Large intestine
Explanation: The correct answer is stomach and pancreas. The stomach secretes pepsin, an enzyme that helps digest proteins, while the pancreas secretes…
Correct answer: Stomach and Pancreas- A. Bile
- B. Gastric juice
- C. Intestinal juice
- D. Pancreatic juice
Explanation: Chyme enters the duodenum from the stomach and so is a mixture of partially digested food and gastric juice. So B is correct.
Correct answer: Gastric juice- A. Epithelial cells → interstitial fluid → capillaries → subclavian vein
- B. Epithelial cells → capillaries → interstitial fluid → thoracic vein
- C. Lacteal → lymph → thoracic lymph duct → subclavian vein
- D. Lacteal → interstitial fluid → capillaries → thoracic vein
Explanation: The correct pathway for the absorption of lipoproteins involves their entry into lacteals, which are lymphatic vessels in the intestinal…
Correct answer: Lacteal → lymph → thoracic lymph duct → subclavian vein- A. Diarrhoea
- B. Dyspepsia
- C. Haemorrhoids
- D. Food poisoning
Explanation: The correct answer is dyspepsia. Gastroesophageal reflux disease (GERD) is a condition where stomach acid frequently flows back into the…
Correct answer: Dyspepsia- A. Larynx
- B. Glottis
- C. Pharynx
- D. Epiglottis
Explanation: The correct answer ispharynx.The pharynx is a muscular structure located at the posterior end of the oral cavity and serves as a conduit…
Correct answer: Pharynx- A. Grind the ingested food
- B. Temporarily store the food
- C. Secrete hydrolytic enzymes
- D. Reabsorb water from the haemolymph
Explanation: The correct answer is Option A.The gizzard in a cockroach is a thick-walled muscular organ that mechanically breaks down food by grinding…
Correct answer: Grind the ingested food- A. Mucus
- B. Sucrose
- C. Amylase
- D. Sodium bicarbonate
Explanation: The correct answer is sucrose. Human saliva contains mucus to lubricate the mouth, amylase to begin the digestion of starches, and sodium…
Correct answer: Sucrose595. The structure that does NOT contribute to the large surface area of the ileum is the presence of
- A. Villi in the inner lining
- B. Microvilli in the epithelium
- C. Muscles in the muscularis layer
- D. Circular folds in the mucosal layer
Explanation: The correct answer ismuscles in the muscularis layerThe muscularis layer's primary function is to aid in the movement of the intestines…
Correct answer: Muscles in the muscularis layer- A. Gastrin
- B. Acetylcholine
- C. Secretin
- D. Cholecystokinins
Explanation: The secretion of bile is primarily stimulated by the hormone cholecystokinin (CCK), rather than secretin.
Correct answer: Cholecystokinins- A. Serosa, longitudinal muscle, mucosa, Sub mucosa
- B. Mucosa, serosa, muscle, epithelium
- C. Serosa, Longitudinal muscles, circular muscles, sub mucosa, mucosa
- D. Serosa, Longitudinal muscles, sub mucosa, mucosa
Explanation: The correct order from outer to inner is Serosa → Longitudinal muscles → Circular muscles → Submucosa → Mucosa.
Correct answer: Serosa, Longitudinal muscles, circular muscles, sub mucosa, mucosa- A. Proteins into amino acids
- B. Glycogen into glucose
- C. Starch into maltose
- D. Fats into vitamins
Explanation: In the mouth, saliva converts starch into maltose. Saliva contains the enzyme amylase, also called ptyalin, and can break down starch into…
Correct answer: Starch into maltose- A. Perform chemical digestion
- B. Stabilize the pH
- C. Act as promoter of ptyallin
- D. Both B and C
Explanation: NaHCO3 is bicarbonate which neutralizes the pH in acidic enviroment.
Correct answer: Both B and C- A. Esophagus and Stomach
- B. Pancreas and liver
- C. Stomach and Duodenum
- D. Stomach and Liver
Explanation: The pancreas and liver are the endocrine pair present in the digestive canal.While the liver is primarily known for its exocrine…
Correct answer: Pancreas and liver