Category: CSIR NET Life Science Previous Year Questions and Solution on Digestive System

Which one of the following statements is true with regard to drug metabolism? (1) The therapeutic window is simply the range of plasma drug concentrations in which the drug has therapeutic benefits without causing extra safety risks due to drug toxicity. (2) Each individual drug molecule is metabolized by a specific drug- metabolizing enzyme that […]

In one study, a group of 5 day rat pups were fed for 3 weeks a diet A and the pups gained weight by 300%. In a second study, when the same diet fed for 3 weeks to rats of 350 gms, they did not gain weight significantly. In a third study, a diet B […]

A person has been suffering from night blindness. On consultation, the doctor advised person to eat carrots and/or cod fish oil. After some time having seen no improvement, doctor gave person vitamin A injection. Still no marked improvement was seen. The doctor mooted several suggestions indicating lack of the following enzymes for failure of treatment: […]

In which of the following conditions is Basal Metabolic Rate (BMR) the lowest? (1) Awake and resting (2) Prolonged starvation (3) Sleep (4) Higher environmental temperature Basal Metabolic Rate (BMR) is the amount of energy the body requires to maintain essential physiological functions while at complete rest. These functions include breathing, circulation, cell production, nutrient […]

Which one is required for vitamin B12 absorption in small intestine? (1) Cobalophilin (2) Hephaestin (3) Hepcidin           (4) Na+-co-transporter Vitamin B12 (cobalamin) absorption in the small intestine is a complex, multi-step process requiring specific proteins for proper uptake. Among these, Cobalophilin, also called R-protein or haptocorrin, plays an essential role in vitamin B12 absorption. Mechanism of Vitamin B12 […]

Which one of the following vitamins is NOT absorbed in the small intestine by Na+ – co-transporters? (1) Thiamine (2) Riboflavin (3) Folic acid (4) Ascorbic acid, Vitamins are essential micronutrients absorbed primarily in the small intestine, where various mechanisms such as passive diffusion, facilitated diffusion, and active transport enable their uptake. Many water-soluble vitamins […]

30. Which one of the following is NOT involved with the absorption of iron in the intestine? (1) Ferroportin 1 (2) Divalent metal transporter (3) Hephaestin (4) Transferrin Iron absorption in the intestine is a tightly regulated process involving several key proteins that facilitate iron uptake, transport, and release into the bloodstream. Among these proteins, […]

An elderly person suffering from calcium deficiency was advised to take calcium rich food and to supplement the diet with vitamin D. The absorption of calcium in the intestine was increased with the supplementation of vitamin-D. Following explanations were offered for this increased calcium absorption by vitamin D: A. The synthesis of Calbindin-D9K and Calbindin-D28K […]

The di- and tripeptides are transported in the enterocytes by peptide transporter l that (1) Na+ (2) Ca++ (3) H+ (4) Cl– The absorption of dietary proteins in the small intestine largely depends on breaking down proteins into smaller peptides—primarily di- and tripeptides—which are then transported into the enterocytes (intestinal epithelial cells). This transport is […]

A person showed the symptoms of diarrhea, gas and pain whenever milk was consumed. The doctor advised the person to take curd instead of milk and subsequently the symptoms mostly disappeared due to this change of dairy product. The following statements are proposed to explain this observation: A. The person has deficiency in the intestinal […]