Tag: digestion and absorption

Questions Related to digestion and absorption

If you have just digested triglyceride molecules, you would expect to find increased amounts of

biology digestion and absorption digestion in small intestine digestive glands and their secretions alimentary canal

  1. glucose

  2. nucleic acids

  3. fatty acids and glycerol

  4. amino acids

Show answer
Correct Option: C
Explanation:

  • Most of the fat in the human diet is in the form of triacylglycerol, which consists of three fatty acids linked to glycerol.
  • In the digestive tract,  triacylglycerol is hydrolyzed by the enzyme pancreatic lipase, to release free fatty acids and monoglycerides. Hence, If you have just digested triglyceride molecules, you would expect to find increased amounts of fatty acids and glycerol.
So, the correct answer is 'fatty acid and glycerol'.

Most of the digestion of lipids in humans takes place in

biology digestion and absorption digestion in small intestine digestive glands and their secretions alimentary canal

  1. mouth

  2. stomach

  3. small intestine

  4. colon

Show answer
Correct Option: C
Explanation:

  • Most lipids that you consume in your diet are fats. Some digestion occurs in your mouth and the stomach but mostly takes place in the small intestine. The purpose of the small intestine is to finish digestion and absorb nutrients. The small intestine is where most chemical digestion takes place. 
  • Many of the digestive enzymes that act in the small intestine are secreted by the pancreas and liver and enter the small intestine via the pancreatic duct. Hence, most of the digestion of lipids in humans takes place in the small intestine.
So, the correct answer is 'small intestine'.

Which of the following associations is incorrect?

biology digestion and absorption digestion in small intestine digestive glands and their secretions alimentary canal

  1. Protein - trypsin

  2. Starch - amylase

  3. Fat - lipase

  4. Maltose - pepsin

Show answer
Correct Option: D
Explanation:

  • Trypsin is produced in the pancreas as an inactive protease trypsinogen. It is a protease found in the digestive system of many vertebrates, where it hydrolyses protein.
  • Amylase is a protein produced by the pancreas and by glands in and around mouth and throat. It helps you break down carbohydrates and starches into sugar.
  • Lipase is a protein produced by the pancreas. It is an enzyme that catalyses the hydrolysis of fats.
  • Pepsin is an endopeptidase produced in the stomach. It breaks down proteins into smaller peptides. Hence, the incorrect association is maltose-pepsin.
So, the correct answer is 'Maltose-pepsin'.

Digestive enzymes are released by pancreas and bile is released by liver in response to the hormone :-

biology digestion and absorption digestion in small intestine digestive glands and their secretions alimentary canal

  1. insulin

  2. zymogen

  3. secretin

  4. cholecystokinin

Show answer
Correct Option: D
Explanation:

CCK is in the duodenum and stimulates the release of digestive enzymes in the pancreas and stimulates the emptying of bile in the gallbladder. This hormone is secreted in response to the fat in the chyme

So, the correct answer is 'Cholecystokinin'

Which one of the following statements is true regarding digestion and absorption of food in humans?

biology digestion and absorption digestion in small intestine digestive glands and their secretions alimentary canal

  1. Oxyntic cells in our stomach secrete the proenzyme pepsinogen

  2. Fructose and amino acids are absorbed through intestinal mucosa with the help of carrier ions like ${K}^{+}$

  3. Chylomicrons are small lipoprotein particles that are transported from the intestine through blood capillaries to various tissues.

  4. About 60% of starch is hydrolysed by salivary amylase in our mouth

Show answer
Correct Option: C
Explanation:

In the intestinal mucosal cells, after absorption, the triglycerides and cholesterol are re-esterified to form chylomicrons. The chylomicrons in turn are secreted into intestinal lymph, enter the blood stream through the thoracic duct and bind to the wall of capillaries in adipose and skeletal tissue.

So, option C is the correct answer.

Which one of the following statements is true regarding digestion and absorption of food on humans?

biology digestion and absorption digestion in small intestine digestive glands and their secretions alimentary canal

  1. Fructose and amino acids are absorbed through intestinal mucosa with the help of carrier ions like ${Na}^{+}$

  2. Chylomicrons are small lipoprotein particles that are transported from intestine into blood capillaries

  3. About 60% of starch in hydrolysed by salivary amylase in our mouth

  4. Oxyntic cells in our stomach secrete the proenzyme pepsinogen

Show answer
Correct Option: A
Explanation:
  • Digestion is the process where complex material in the food is broken down to simple nutrients and molecules so that they can be absorbed and circulated in the body. 
  • The digestion of the food starts in the buccal cavity of the organism where the enzyme amylase is secreted. This enzyme is used for the digestion of the starch present in the food. Though much of the starch is digested in the mouth it is divided in disaccharide units of carbohydrates which will be further digested in intestine. 
  • The food from the buccal cavity is taken to the stomach via oesophagus where the food is stored for about 3 to 4 hours and mixed with the hydrochloric acid which is secreted by the oxyntic cell present in the mucosa wall of the stomach. This will give the food a acidic pH which is necessary for the activation of the pepsin enzyme which are there for digestion of proteins to peptides. 
  • This acidic chyme of the stomach is to be transported for further digestion in the intestine where it is mixed with the alkaline secretion released from the liver and pancreas. 
  • In intestine the food components such as carbohydrates, proteins, lipids etc are digested to small absorbable molecules. 
  • The carbohydrates are digested to monosaccharides glucose, fructose, galactose, proteins are broken down to amino acids and lipids are reduced to small fat globules called microns. 
  • Some of these components are already present in the cell fo the body surrounding the digestive track. So for the transport of molecules ion transporters are used sach as sodium ion transporter, etc. 
  • Glucose is easily digested compared to other molecules of monosaccharides as it is easily soluble in water. Monosaccharides such as fructose and amino acid units are transported to the blood stream along with the sodium ions that are transportedby the sodium ion transporter. 
  • Fat globules are transported by the lacteal cells that are present in the intestine mucosa of the intestine. Chylomicrons are also used to transport fat to liver and adipose tissue where it can be stored. 
  • Therfore for the following question option A and C are correct. 

Digestion of food
In humans one of the constituents of the pancreatic juice which is poured into the duodenum is 

biology digestion and absorption digestion in small intestine digestive glands and their secretions alimentary canal

  1. trypsinogen

  2. chymotrypsin

  3. trypsin

  4. enterokinase.

Show answer
Correct Option: A

Match the enzymes with their respective substrates and choose the right one among options given.

Column I Column II
A. Lipase  (i) Dipeptides 
B. Nuclease  (ii) Fats
C. Carboxypeptidase  (iii) Nucleic acids
D. Dipeptidases  (iv) Proteins, peptones and proteoses 
biology digestion and absorption digestion in small intestine digestive glands and their secretions alimentary canal

  1. A-(ii), B-(iii), C-(i), D-(iv)

  2. A-(iii), B-(iv), C-(ii), D-(i)

  3. A-(iii), B-(i), C-(iv), D-(ii)

  4. A-(ii), B-(iii), C-(iv), D-(i)

Show answer
Correct Option: D
Explanation:

(A) Lipase - Fats

(B) Nuclease - Nucleic acids
(C) Carboxypeptidase - Proteins, peptones and proteoses
(D) Dipeptidases - Dipeptides
So, the correct answer is (d).

Rennin and lactase, the enzymes required to digest milk, disappear in the human body by the age of

biology digestion and absorption digestion in small intestine digestive glands and their secretions alimentary canal

  1. Five

  2. Three

  3. Two

  4. Eight

Show answer
Correct Option: B
Explanation:

Rennin is an aspartic endopeptidase belonging to MEROPS A1 family. It is produced by newborn ruminant animals in the lining of the abomasum to curdle the milk they ingest, allowing a longer residence in the bowels and better absorption. It is widely used in the production of cheese. Lactase is an enzyme produced by many organisms.  Lactase can be purchased as a food supplement, and is added to milk to produce "lactose-free" milk products. Lactase is the enzymes that splits lactose (milk sugar) into glucose and galactose. The enzymes necessary to break down and digest milk (rennin and lactase) are all gone by the age of three in most humans. 

So the correct option is 'three'.

Which of the following processes is helped by bile salts?

biology digestion and absorption digestion in small intestine digestive glands and their secretions alimentary canal

  1. Nucleic acid $\overset{Nuclease}{\rightarrow}$ Nucleotides $\overset{Nucleotidase}{\rightarrow}$ Nucleosides $\overset{Nucleosidase}{\rightarrow}$ Sugars + bases

  2. Sucrose $\overset{Sucrase}{\rightarrow}$ Glucose + Fructose

  3. Fats $\overset{Lipase}{\rightarrow}$ Diglyceides $\overset{Lipase}{\rightarrow}$ Monoglycerides

  4. Proteins, peptones, proteoses $\xrightarrow[Carboxypeptidase]{Trypsin/Chymotrypsin}$ Dipeptides

Show answer
Correct Option: C
Explanation:

The correct answer is (c).