NEET Previous Year Questions(2014-23): Digestion & Absorption (Old NCERT) PDF Download

Q.1.  List I with List II

Choose the correct answer from the options given below:
(a) A-IV, B-III, C-II, D-I
(b) A-II, B-I, C-III, D-IV
(c) A-III, B-I, C-IV, D-II
(d) A-II, B-IV, C-I, D-III

Correct Answer is Option (c)

Option (3) is the correct answer because gastric glands have three major types of cells namely

• Mucus neck cells which secrete mucus 
• Peptic or chief cells which secrete the proenzyme pepsinogen
• Parietal or oxyntic cells which secrete HCl and intrinsic factor for absorption of vitamin B12.

Q.2. Once the undigested and unabsorbed substances enter the caecum, their backflow is prevented by
(a) Sphincter of Oddi
(b) Ileo-caecal valve
(c) Gastro-oesophageal sphincter
(d) Pyloric sphincter

Correct Answer is Option (b)

Option (2) is the correct answer because the undigested food (faeces) enters into caecum of the large intestine through ileo-caecal valve, which prevents the backflow of the faecal matter.

Option (3) is not the answer because a muscular sphincter i.e., the gastro-oesophageal sphincter regulates the opening of oesophagus into the stomach.

Option (4) is not the answer because pyloric sphincter regulates the opening in between stomach and duodenum.

Option (1) is not the answer because the opening of common hepato-pancreatic duct is guarded by sphincter of Oddi.

Q.3. Given below are two statements:   [NEET 2022]
Statement I: Fatty acids and glycerols cannot be absorbed into the blood.
Statement II: Specialized lymphatic capillaries called lacteals carry chylomicrons into lymphatic vessels and ultimately into the blood.
In the light of the above statements, choose the most appropriate answer from the options given below:
(a) Both Statement I and Statement II are incorrect
(b) Statement I is correct but Statement II is incorrect
(c) Statement I is incorrect but Statement II is correct
(d) Both Statement I and Statement II are correct

Correct Answer is Option (d)
Statement I: Fatty acids and glycerols cannot be absorbed into the blood due to their insoluble nature. So, statement I is correct.
Statement II: Fatty acids and glycerols are absorbed into intestinal cells with the help of micelles. Once inside the intestinal cells, they are packed into protein fat globules called chylomicrons. These then enter the lymph capillaries called lacteals and the lymph when draining in the blood transports fat into the blood. So, statement II is correct.

Q.4. Which of the following functions is not performed by secretions from salivary glands?   [NEET 2022]
(a) Digestion of complex carbohydrates
(b) Lubrication of oral cavity
(c) Digestion of disaccharides
(d) Control bacterial population in mouth

Correct Answer is Option (c)
Salivary glands are one of the most important glands in our digestive systems which produces saliva. Saliva contains a carbohydrate digesting enzyme called salivary amylase (ptyalin). This enzyme help in the digestion of starch in the oral cavity. Starches are complex carbohydrates formed by longer saccharide chains of amylose and amylopectin. Saliva also helps in lubrication of the buccal cavity. Lysozymes present in saliva protects against bacterial invasion. The digestion of disaccharides and some oligosaccharides is undertaken by a number of small intestinal brush border enzymes like sucrase-isomaltase, lactase, maltase-glucoamylase and trehalase.

Q.5. Match list - I with the list - II.   [NEET 2022]

Choose the correct answer from the options given below:
(A) (a) - (i), (b) - (ii), (c) - (iii), (d) - (iv 
(B) (a) - (ii), (b) - (i), (c) - (iv), (d) - (iii) 
(C) (a) - (iii), (b) - (iv), (c) - (ii), (d) - (i) 
(D) (a) - (iv), (b) - (iii), (c) - (i), (d) - (ii)

Correct Answer is Option (d)
The bronchioles are lined by simple columnar to the cuboidal epithelium. Goblet cells are simple columnar epithelial cells that secrete mucus on the surface of mucous membranes of organs and are glandular in nature. Tendons and ligaments are made of dense regular connective tissue because they need a strong structure. Adipose tissues are loose connective tissues that are made up of fat cells called adipose cells or adipocytes.

Q.6. Succus entericus is referred to as:    [NEET 2021]
(a) Gastric juice
(b) Chyme
(c) Pancreatic juice
(d) Intestinal juice

Correct Answer is Option (d)

The intestinal mucosal epithelium has goblet cells which secrete mucus.The secretions of the brush border cells of the mucosa along with the secretions of the goblet cells constitute the intestinal juice or succus entericus.
NCERT Reference: Page no. 262 (last paragraph) of chapter 16 of NCERT

Q.7. Sphincter of oddi is present at :    [NEET 2021]
(a) Gastro-oesophageal junction
(b) Junction of jejunum and duodenum
(c) Ileo-caecal junction
(d) Junction of hepato-pancreatic duct and duodenum

Correct Answer is Option (d)

The bile duct and the pancreatic duct open together into the duodenum as the common hepato-pancreatic duct which is guarded by a sphincter called the sphincter of Oddi.
NCERT Reference: Page no. 261 (first paragraph) of chapter 16 of NCERT

Q.8. The enzyme enterokinase helps in conversion of      [NEET 2020]
(a) Caseinogen into casein
(b) Pepsinogen into pepsin
(c) Protein into polypeptides
(d) Trypsinogen into trypsin

Correct Answer is Option (d) 
Trypsinogen is present in an inactive form in pancreatic juice. So enterokinase enzyme converts inactive trypsinogen to active trypsin. This in turn activates the other enzymes in the pancreatic juice.

Enterokinase Enzyme is a type of Brush Border Enzyme.

NCERT Reference: Page no. 262 (2nd last paragraph) of chapter 16 of NCERT

Q.9. Identify the correct statement with reference to the human digestive system.     [NEET 2020]
(a) Ileum is a highly coiled part
(b) Vermiform appendix arises from duodenum
(c) Ileum opens into small intestine 
(d) Serosa is the innermost layer of the alimentary canal.

Correct Answer is Option (a)
(a) Small intestine is distinguishable into three regions, a ‘U’ shaped duodenum, a long coiled middle portion jejunum and a highly coiled ileum.
(b) A narrow finger-like tubular projection, the vermiform appendix which is a vestigial organ, arises from the caecum.
(c) Ileum opens into the large intestine.
(d) The wall of the alimentary canal possesses four layers from outer to inner namely serosa, muscularis, submucosa and mucosa. Serosa is the outermost layer and mucosa is the innermost layer.
NCERT Reference: Page no. 259 of chapter 16 of NCERT

You can also check this video on alimentary canal for understanding the topic in depth
Video: Alimentary Canal: Digestion & Absorption
Video: Anatomy of Alimentary Canal

Q.10. Goblet cells of alimentary canal are modified from:     [NEET 2020]
(a) Chondrocytes 
(b) Compound epithelial cells
(c) Squamous epithelial cells
(d) Columnar epithelial cells 

Correct Answer is Option (d)
Goblet cells are modified columnar epithelial cells. These are found in the lining of organs like respiratory tract and intestine.
NCERT Reference: Page no. 260 (1st paragraph) of chapter 16 of NCERT

Q.11. Match the following structures with their respective location in organs.

Select the correct option from the following:    [NEET 2019]

Correct Answer is Option (d)
Crypts of Lieberkhn are present in the small intestine, Glisson's capsule is present in the liver. Islets of Langerhans constitute the endocrine portion of pancreas. Brunner's glands are found in the submucosa of duodenum.
So, the correct answer is '(A)-(iii), (B)-(iv), (C)-(i), (D)-(ii)
NCERT Reference: Page no. 260 (1st paragraph), 260 (last paragraph), 262 (last paragraph) respectively of chapter 16 of NCERT

Q.12. Identify the cells whose secretion protects the lining of the gastrointestinal tract from various enzymes.    [NEET 2019]
(a) Duodenal cells
(b) Chief cells
(c) Goblet cells
(d) Oxyntic cells

Correct Answer is Option (c) 
Goblet cells or mucous cells are present throughout the epithelium of gastric glands and secrete mucus, which protects the gastrointestinal lining from enzymatic action.

Goblet Cell

NCERT Reference: Page no. 262 (last paragraph) of chapter 16 of NCERT

Q.13. Match the items given in Column I with those in Column II and choose the correct option.    [NEET 2019]

(a) A-iii, B-iv, C-ii, D-i
(b) A-iv, B-iii, C-i, D-ii
(c) A-iv, B-iii, C-ii, D-i
(d) A-iii, B-iv, C-i, D-ii

Correct Answer is Option (d) 

• Rennin, also called chymosin, is a protein-digesting enzyme that curdles milk by transforming caseinogen into insoluble casein; it is found only in the fourth stomach of cud-chewing animals, such as cows.
• Enteropeptidase (also called enterokinase) is an enzyme produced by cells of the duodenum and is involved in digestion in humans and other animals. Enteropeptidase converts trypsinogen (a zymogen) into its active form trypsin, resulting in the subsequent activation of pancreatic digestive enzymes.
• The intrinsic factor (IF) is a glycoprotein produced by the parietal cells (oxyntic cells) located at the gastric body and fundus. Intrinsic factor plays a crucial role in the transportation and absorption of the vital micronutrient vitamin B12 (cobalamin, Cbl) by the terminal ileum.
• Fructose moves entirely via facilitated diffusion. The process utilises a different transporter to glucose when entering the enterocytes, however, both fructose and glucose utilise the same transporter to exit the enterocyte into the capillaries.

Q.14. Which of the following terms describes human dentition?    [NEET 2018]
(a) Thecodont, Diphyodont, Homodont
(b) Thecodont, Diphyodont, Heterodont
(c) Pleurodont, Monophyodont, Homodont
(d) Pleurodont, Diphyodont, Heterodont

Correct Answer is Option (b)

• The majority of mammals, including human beings, erupt two sets of teeth during their lifetime, a set of temporary milk or deciduous teeth that is replaced by a set of permanent or adult teeth. This type of dentition is called diphyodont. 
• An adult human has 32 permanent teeth which are of four different types (heterodont dentition), namely, incisors (1), canines (C), premolars (PM), and molars (M). Teeth are embedded in the sockets of the jawbones, which represents thecodont dentition.

NCERT Reference: Page no. 257 and 258 topic “16.1.1 Alimentary Canal” of chapter 16 of NCERT

Q.15. Which of the following gastric cells indirectly help in erythropoiesis?    [NEET 2018]
(a) Chief cells
(b) Mucous cells
(c) Goblet cells
(d) Parietal cells

Correct Answer is Option (d)

Parietal cells indirectly help in erythropoiesis. Erythropoiesis is the phenomenon wherein human erythrocytes are formed. The process is stimulated by a hormone of the kidney (Juxtaglomerular cells) which is produced during hypoxia known as erythropoietin. The site of Erythropoiesis is in the bone marrow, here the differentiation of the hematopoietic stem cells occurs, which gradually get rid of its nuclei to turn into reticulocytes. The process involves a special functional differentiation and expression of genes.

Q.16. Which cells of ‘Crypts of Lieberkuhn’ secrete antibacterial lysozyme?   [NEET 2017]
(a) Paneth cells
(b) Zymogen cells
(c) Kupffer cells
(d) Argentaffin cells

Correct Answer is Option (a)

Paneth cells, present in the bottom of crypts of Lieberkuhn, are rich in zinc and contain acidophilic granules. There is evidence that these cells secrete antibacterial lysozyme. Zymogen cells or peptic cells are present in the stomach and secrete pepsinogen. Kupffer cells are present in the liver. They are phagocytic in nature and engulf disease-causing microorganisms, dead cells, etc.
Argentaffin cells, found in crypts of Lieberkuhn, synthesise hormone secretin and 5 - hydroxytryptamine.

Q17. Which of the following options best represents the enzyme composition of pancreatic juice?    [NEET 2017]
(a) Amylase, Pepsin, Trypsinogen, Maltase
(b) Peptidase, Amylase, Pepsin, Rennin
(c) Lipase, Amylase, Trypsinogen, Procarboxypeptidase
(d) Amylase, Peptidase, Trypsinogen, Rennin

Correct Answer is Option (c)
The pancreatic juice contains sodium bicarbonate, three proenzymes: trypsinogen, chymotrypsinogen, and procarboxypeptidase and some enzymes such as elastase, pancreatic a-amylase, DNase, RNase and pancreatic lipase. It helps in the digestion of starch, proteins, fats, and nucleic acids.
NCERT Reference: Page no. 262 (3rd paragraph) of chapter 16 of NCERT

Q.18. A baby boy aged two years is admitted to playschool and passes through a dental check-up. The dentist observed that the boy had twenty teeth. Which teeth were absent?    [NEET 2017]
(a) Canines
(b) Pre-molars
(c) Molars
(d) Incisors

Correct Answer is Option (b)
Boy aged two years will have milk teeth of man including 8 incisors, 4 canines, 8 molars. Premolars are absent.
Note: This question is reasoning and understanding based on the topic.
NCERT Reference: Page no. 257 and 258 “Alimentary canal” chapter 16 of NCERT for understanding the topic in detail

Q.19. Which hormones do stimulate the production of pancreatic juice and bicarbonate?     [NEET 2016]
(a) Angiotensin and epinephrine
(b) Gastrin and insulin
(c) Cholecystokinin and secretin
(d) Insulin and glucagon

Correct Answer is Option (c)
Cholecystokinin pancreozymin (CCKPZ) is a hormone secreted from the small intestine. It stimulates the gall bladder to release bile and the pancreas to secrete and release digestive enzymes in the pancreatic juice. Hormone secretin is secreted from the duodenum and releases bicarbonates in the pancreatic juice. It also increases the secretion of bile and decreases gastric secretion and motility.

Q20. In the stomach, gastric acid is secreted by the    [NEET 2016]

(a) Gastrin secreting cells
(b) Parietal cells
(c) Peptic cells
(d) Acidic cells

Correct Answer is Option (b)

The main constituent of gastric acid is hydrochloric acid produced by parietal cells (also called oxyntic cells) in the stomach's gastric glands.
NCERT Reference: Refer page no. 262 (1st paragraph) of chapter 16 of NCERT

Q.21. Which of the following guards the opening of the hepatopancreatic duct into the duodenum?      [NEET 2016] 

(a) Semilunar valve
(b) Ileocaecal valve
(c) Pyloric sphincter
(d) Sphincter of Oddi

Correct Answer is Option (d)

The sphincter of Oddi (also hepatopancreatic sphincter or Glisson's sphincter), abbreviated as SO, is a muscular valve that in some animals, including humans, controls the flow of digestive juices (bile and pancreatic juice) through the ampulla of Vater into the second part of the duodenum.

Q.22. Which of the following statements is not correct?        [NEET 2015]

(a) Goblet cells are present in the mucosa of the intestine and secrete mucus.
(b) Oxyntic cells are present in the mucosa of the stomach and secrete HCl.
(c) Acini are present in the pancreas and secrete carboxypeptidase.
(d) Brunner's glands are present in the submucosa of the stomach and secrete pepsinogen.

Correct Answer is Option (d)

The Brunner's glands are present in the submucosa of the small intestine and secrete an alkaline fluid rich in mucin that protects the duodenal surface of the small intestine from the action of the acidic chyme.
NCERT Reference: Page no. 262 (last paragraph) of chapter 16 of NCERT

Q.23. Gastric juice of infants contains:      [NEET 2015]

(a) Nuclease, pepsinogen, lipase
(b) Pepsinogen, lipase, rennin
(c) Amylase, rennin, pepsinogen
(d) Maltase, pepsinogen, rennin

Correct Answer is Option (b)

Gastric juice of infants contains pepsinogen, lipase, and rennin. Gastric juice does not contain amylase, maltase & nuclease.
NCERT Reference: Page no. 262 (2nd paragraph) of chapter 16 of NCERT

Q.24. The primary dentition in human differs from permanent dentition in not having one of the following types of teeth:    [NEET 2015] 

(a) Premolars
(b) Molars
(c) Incisors
(d) Canine

Correct Answer is Option (a)
The premolar teeth, or bicuspids, are transitional teeth located between the canine and molar teeth. There are two premolars per quadrant in the permanent set of teeth in humans, making eight premolars total in the mouth. The dental formula for milk teeth is 2102/2102 so premolars are absent in the primary dentition.

Q.25. The initial step in the digestion of milk in humans is carried out by    [NEET 2014] 
(a) Lipase
(b) Trypsin
(c) Rennin
(d) Pepsin

Correct Answer is Option (d)
In humans, the milk protein digesting enzyme in the stomach is pepsin. In calves it is rennin. It is also present in small amounts in human infants but not adults. Pepsin acts on water soluble 'caseinogen' (milk protein) to form soluble 'casein'  This combines with calcium salts to form insoluble calcium paracaseinate, which gets readily digested  enzymatically.
NCERT Reference: Page no. 262 (2nd paragraph) of chapter 16 of NCERT

Q.26. Fructose is absorbed into the blood through mucosa cells of the intestine by the process called:    [NEET 2014]
(a) Active transport
(b) Facilitated transport
(c) Simple diffusion
(d) Co-transport mechanism

Correct Answer is Option (b) 
Facilitated transport is a form of passive transport in which materials are moved across the plasma membrane by a transport protein down their concentration gradient e.g. glucose, fructose and amino acids. Hence, it does not require energy.
NCERT Reference: Page no. 264 of topic “16.3 ABSORPTION OF DIGESTED PRODUCTS” of chapter 16 of NCERT