Biology Multiple Choice Questions on “Disorders in Digestive System – 1”.
1. What is the most common ailment of the alimentary canal?
a) Inflammation
b) Jaundice
c) Diarrhoea
d) Vomiting
Answer: a
Clarification: The inflammation of the alimentary canal is the most common ailment due to bacterial or viral infections. The infections are also caused by parasites of the intestine like tapeworm, roundworm, etc.
2. Which of the following is a symptom of jaundice?
a) Bile salts deposit in the liver
b) Bile salts deposit in eyes
c) Bile pigments deposit in the liver
d) Bile pigments deposit in the eyes
Answer: d
Clarification: In jaundice, the liver is affected, skin and eyes turn yellow due to the deposition of bile pigments particularly bilirubin. It is a waste material that remains in the bloodstream after iron is removed from the blood.
3. Where is the vomiting centre present in our bodies?
a) Medulla
b) Pons
c) Cerebellum
d) Hypothalamus
Answer: a
Clarification: Vomiting is the ejection of stomach contents through the mouth. This reflex action is controlled by the vomiting centre in the medulla. A feeling of nausea precedes vomiting.
4. Which of the following is the symptom of diarrhoea?
a) Limited frequency of the bowel movement
b) No bowel movement
c) Abnormal frequency of bowel movement
d) The normal frequency of bowel movement
Answer: c
Clarification: The abnormal frequency of bowel movement and increased liquidity of the faecal discharge is known as diarrhoea. It reduces the absorption of food.
5. In constipation, there is increased liquidity of the faecal matter.
a) True
b) False
Answer: b
Clarification: In constipation, the faeces are retained within the colon as the bowel movement occurs irregularly. Increased fluidity of the faecal matter is the symptom of diarrhoea.
6. What is a bomb calorimeter?
a) Open metal chamber
b) Open brass chamber
c) The closed metal chamber filled with oxygen
d) The closed metal chamber filled with nitrogen
Answer: d
Clarification: Bomb calorimeter is a closed metal chamber which is filled with oxygen. The amount of heat liberated from the complete combustion of 1 g food in a bomb calorimeter is its gross calorific value.
7. What is the physiologic value of food?
a) The actual amount of energy combustion of 1 g of food
b) The actual amount of energy combustion of 1 Kg of food
c) The actual amount of energy combustion of 1 mg of food
d) Amount of complete combustion of 1 g food in a bomb calorimeter
Answer: a
Clarification: The actual amount of energy combustion of 1 g of food is the physiologic value of food. Physiologic value of fats and carbohydrates is 9 kcal/g and 4 kcal/g respectively.
8. What is the gross calorific value of proteins?
a) 4 kcal/g
b) 5.65 kcal/g
c) 9 kcal/g
d) 9.45 kcal/g
Answer: b
Clarification: The gross calorific value of proteins is 5.65 kcal/g while the physiologic value of proteins is 4 kcal/g. The gross calorific value of carbohydrates and fats is 4.1 kcal/g and 9.45 kcal/g respectively.
9. What is meant by absorption of food?
a) End products of digestion are thrown out of the body
b) End products of digestion are egested out of the body
c) End products of digestion are transported to the body
d) End products of digestion are passed through the intestinal mucosa
Answer: d
Clarification: Absorption is the process by which the end products of digestion pass through the intestinal mucosa into the blood or lymph. It is carried out by passive, active or facilitated transport mechanisms.
10. Which of the following is not absorbed by simple diffusion?
a) Glucose
b) Amino acids
c) Sodium ions
d) Chloride ions
Answer: c
Clarification: Sodium ions are not absorbed by simple diffusion. Glucose, amino acids and some electrolytes like chloride ions are generally absorbed by simple diffusion. The rate or passage of these ions depends upon the concentration gradients.
11. Water is transported through a facilitated diffusion mechanism.
a) True
b) False
Answer: b
Clarification: Transport of water depends upon the osmotic gradient. However, some substances like glucose and amino acids are absorbed with the help of carrier proteins. This mechanism is called facilitated transport.
12. Which of the following is transported through active transport?
a) Sodium ions
b) Chloride ions
c) Fatty acids
d) Glycerol
Answer: a
Clarification: Active transport occurs against the concentration gradient and hence requires energy. Various nutrients like amino acids, monosaccharides like glucose and electrolytes like sodium ions are absorbed into the blood by this mechanism.
13. What are chylomicrons?
a) Very large protein-coated fat molecules
b) Very large fat coated protein molecules
c) Very small protein-coated fat molecules
d) Very small fat coated protein molecules
Answer: c
Clarification: Fatty acids and glycerol being insoluble, cannot be absorbed into the blood. They are first incorporated into micelles and then are reformed into very small protein-coated fat molecules called chylomicrons.
14. Which is the principal organ for absorption?
a) Mouth
b) Stomach
c) Small intestine
d) Large intestine
Answer: c
Clarification: The principal organ for the absorption of nutrients in the small intestine. The digestion is completed here and the final products of digestion are absorbed through the mucosa into the bloodstream and the lymph.
15. What initiates a signal for defaecation?
a) Faeces in the colon
b) Faeces in the rectum
c) Faeces in the caecum
d) Faeces in the ileum
Answer: b
Clarification: The digestive wastes, solidified into coherent faeces in the rectum initiate a neural reflex causing an urge or desire for its removal. Defaecation is a voluntary process and is carried out by mass peristaltic movements.