NEET UG - Digestion and absorption - human alimentary canal and digestive glands Online Test (MCQ Quiz)

1. The process of breaking down complex food substances into simpler, absorbable forms is called:

A) Ingestion B) Digestion C) Absorption D) Egestion

2. Which of the following is the primary function of the human alimentary canal?

A) Circulation of blood B) Digestion and absorption of food C) Excretion of metabolic waste D) Regulation of body temperature

3. The alimentary canal begins with the anterior opening, the:

A) Anus B) Mouth C) Pharynx D) Oesophagus

4. The main function of mastication (chewing) in the mouth is to:

A) Sterilize food particles B) Break down food mechanically C) Increase the surface area for enzyme action D) Dissolve food particles in saliva

5. Saliva is secreted by three pairs of salivary glands. Which of these is located just in front of the ear?

A) Sublingual gland B) Submandibular gland C) Parotid gland D) Palatine gland

6. The enzyme present in saliva that begins the chemical digestion of carbohydrates is:

A) Pepsin B) Trypsin C) Amylase D) Lipase

7. Salivary amylase, also known as ptyalin, breaks down starch into:

A) Glucose B) Fructose C) Maltose D) Lactose

8. The tongue is a muscular organ that helps in:

A) Swallowing and tasting food B) Mixing food with saliva and swallowing C) Chewing and tasting food D) Digesting carbohydrates

9. The muscular walls of the pharynx play a role in:

A) Mechanical digestion B) Chemical digestion C) Swallowing (deglutition) D) Absorption of nutrients

10. The flap of cartilage that prevents the entry of food into the trachea during swallowing is called the:

A) Glottis B) Epiglottis C) Larynx D) Pharynx

11. The oesophagus is a muscular tube that connects the pharynx to the:

A) Duodenum B) Stomach C) Small intestine D) Large intestine

12. The movement of food through the oesophagus and other parts of the alimentary canal is facilitated by wave-like muscular contractions known as:

A) Segmentation B) Peristalsis C) Mass movements D) Churning

13. The stomach is a J-shaped organ located in the upper part of the abdomen, primarily responsible for:

A) Absorption of water B) Digestion of proteins C) Storage and initial digestion of food D) Secretion of bile

14. The innermost lining of the stomach contains folds called rugae, which:

A) Increase surface area for absorption B) Allow the stomach to expand C) Secrete gastric juices D) Protect the stomach wall from acid

15. Gastric juice is secreted by glands in the stomach wall. The main enzyme responsible for protein digestion in the stomach is:

A) Trypsinogen B) Pepsin C) Chymotrypsin D) Carboxypeptidase

16. Pepsinogen, an inactive enzyme precursor, is converted to its active form, pepsin, by:

A) Bile salts B) Hydrochloric acid C) Secretin D) Enterokinase

17. Hydrochloric acid (HCl) in the stomach serves multiple functions, including:

A) Emulsifying fats B) Activating pepsinogen and killing microbes C) Breaking down carbohydrates D) Neutralizing acidic chyme

18. The semi-digested food mixture that leaves the stomach and enters the small intestine is called:

A) Bolus B) Chyme C) Feces D) Micelles

19. The small intestine is the principal site for the completion of digestion and the primary site for the absorption of nutrients. It is divided into three parts: duodenum, jejunum, and:

A) Ileum B) Colon C) Rectum D) Caecum

20. The first part of the small intestine, which receives chyme from the stomach and bile and pancreatic juice from the liver and pancreas, is the:

A) Jejunum B) Ileum C) Duodenum D) Caecum

21. The inner lining of the small intestine is characterized by numerous finger-like projections called villi and microvilli, which:

A) Secrete digestive enzymes B) Propel food forward C) Greatly increase the surface area for absorption D) Neutralize stomach acid

22. Each villus in the small intestine contains a network of capillaries and a large lymphatic vessel called a:

A) Sinusoid B) Lacteal C) Capillary bed D) Venule

23. Which of the following digestive glands is the largest gland in the body?

A) Pancreas B) Salivary glands C) Liver D) Gastric glands

24. The liver produces bile, which is stored and concentrated in the:

A) Pancreas B) Gall bladder C) Spleen D) Appendix

25. Bile plays a crucial role in fat digestion by:

A) Breaking down fats into fatty acids and glycerol B) Activating lipase enzymes C) Emulsifying fats into smaller droplets D) Absorbing fat-soluble vitamins

26. The pancreas is a gland that secretes both exocrine (digestive enzymes) and endocrine (hormones) substances. Its exocrine function involves secreting:

A) Insulin and glucagon B) Pancreatic juice containing various enzymes C) Bile D) Hydrochloric acid

27. Pancreatic juice contains enzymes like amylase, lipase, and proteases (e.g., trypsinogen, chymotrypsinogen). Trypsinogen is activated to trypsin by an enzyme secreted by the intestinal mucosa called:

A) Enterokinase B) Secretin C) Cholecystokinin D) Enterocrinin

28. The intestinal juice, also known as succus entericus, is secreted by the glands in the intestinal wall and contains enzymes that complete the digestion of:

A) Proteins and carbohydrates B) Fats and carbohydrates C) Proteins, carbohydrates, and fats D) Only nucleic acids

29. The final products of carbohydrate digestion are:

A) Amino acids B) Fatty acids and glycerol C) Monosaccharides (e.g., glucose, fructose) D) Nucleotides

30. The final products of protein digestion are:

A) Monosaccharides B) Fatty acids and glycerol C) Amino acids D) Nucleosides

31. Fats are digested by lipases into:

A) Glucose and fructose B) Amino acids C) Fatty acids and glycerol D) Nucleotides

32. Absorption of simple sugars and amino acids primarily occurs in the:

A) Stomach B) Duodenum and jejunum C) Ileum D) Large intestine

33. The absorption of digested fats, mainly in the form of fatty acids and glycerol, involves their re-esterification into triglycerides within the intestinal cells and packaging into lipoprotein particles called:

A) Chylomicrons B) Micelles C) VLDL D) HDL

34. Fat-soluble vitamins (A, D, E, K) are absorbed along with:

A) Water B) Minerals C) Fats D) Proteins

35. Water-soluble vitamins (B complex and C) are absorbed by:

A) Facilitated diffusion or active transport B) Simple diffusion C) Pinocytosis D) Endocytosis

36. The large intestine primarily absorbs:

A) Most of the nutrients B) Water and electrolytes C) All digested food D) Vitamins synthesized by bacteria

37. The final stage of digestion involves the elimination of indigestible food material through the anus, a process called:

A) Absorption B) Assimilation C) Egestion D) Secretion

38. The structure that controls the opening of the stomach into the duodenum is the:

A) Pyloric sphincter B) Oesophageal sphincter C) Ileocecal valve D) Anal sphincter

39. Which hormone stimulates the secretion of gastric juice from the stomach wall?

A) Secretin B) Cholecystokinin C) Gastrin D) Enterogastrone

40. The hormone secretin primarily stimulates the pancreas to release:

A) Enzymes B) Bicarbonate-rich pancreatic juice C) Bile D) Hydrochloric acid

41. Cholecystokinin (CCK) stimulates the gall bladder to contract and release bile, and also stimulates the pancreas to release:

A) Bicarbonate ions B) Enzyme-rich pancreatic juice C) Insulin D) Glucagon

42. The vermiform appendix is a small, finger-like outgrowth attached to the:

A) Stomach B) Jejunum C) Caecum D) Rectum

43. The primary role of the caecum in humans is:

A) Digestion of cellulose B) Absorption of water C) Storage of feces D) Fermentation of indigestible material

44. The rectum is the final section of the large intestine, terminating at the:

A) Caecum B) Colon C) Anus D) Sigmoid colon

45. The muscular sphincter that regulates the exit of feces from the body is the:

A) Pyloric sphincter B) Internal anal sphincter C) External anal sphincter D) Both internal and external anal sphincters

46. The process of breaking down food into absorbable units is called digestion, while the process of moving these units from the lumen of the intestine into the blood or lymph is called:

A) Ingestion B) Egestion C) Absorption D) Assimilation

47. Which part of the small intestine is mainly responsible for the absorption of vitamin B12 and bile salts?

A) Duodenum B) Jejunum C) Ileum D) Colon

48. The enzyme lactase, found in the intestinal juice, breaks down lactose into:

A) Glucose and glucose B) Glucose and galactose C) Galactose and fructose D) Two molecules of lactose

49. The absorption of certain electrolytes and minerals, like iron and calcium, is an active process occurring mainly in the:

A) Stomach B) Duodenum and jejunum C) Ileum D) Large intestine

50. The liver receives blood from the hepatic artery and the hepatic portal vein. The hepatic portal vein carries blood rich in absorbed nutrients from the:

A) Stomach and oesophagus B) Small intestine, large intestine, stomach, and spleen C) Heart and lungs D) Kidneys and bladder

Digestion and absorption - human alimentary canal and digestive glands - Online Test

Test Results