1. Calcitriol is the biologically active form of which among the following Vitamins?
[A] Vitamin B
[B] Vitamin C
[C] Vitamin D
[D] Vitamin E
Show Answer
Correct Answer: C [Vitamin D]
Notes:
Calcitriol is the biologically active form of Vitamin D. It is normally made in the kidney. It is used to treat diseases like hypoparathyroidism, osteoporosis, osteomalacia, and familial hypophosphatemia.
2. Which among the following correctly denotes Net Reproduction Rate?
[A] Average number of children that would be born to a woman over her lifetime
[B] Average number of children that would be born to a couple over their life time
[C] Birth Rate — Death rate
[D] The rate at which women are replaced by daughters who will have children
Show Answer
Correct Answer: D [The rate at which women are replaced by daughters who will have children]
Notes:
In population ecology and demography, the net reproduction rate is defined as the average number of offspring that would be born to a female if she passed through her fertility age. Or simply The rate at which women are replaced by daughters who will have children.
3. The Indian Pipe Plant or Monotrapa can be best placed in which among the following groups?
[A] Parasite
[B] Saprophyte
[C] Insectivorous
[D] Lithophyte
Show Answer
Correct Answer: B [Saprophyte]
Notes:
Pipe Plant is a total saprophyte i.e. thrives on dead or decayed organic matter
4. Which process enables the Peepal tree to release oxygen at night?
[A] Crassulacean Acid Metabolism
[B] C3 Photosynthesis
[C] C4 Photosynthesis
[D] Carbon cycle re-balancing
Show Answer
Correct Answer: A [Crassulacean Acid Metabolism]
Notes:
The Peepal tree uses Crassulacean Acid Metabolism (CAM) photosynthesis, allowing CO₂ uptake at night and oxygen release, a trait seen in some succulents and epiphytes to minimize water loss. CAM enables the Peepal to continue gas exchange during the night, unlike typical C3 or C4 plants.
5. Strontium-90, as a source of health issues after a nuclear disaster is most dangerous for which among the following organs of Human Body?
[A] Liver
[B] Blood
[C] Skin
[D] Bones
Show Answer
Correct Answer: D [ Bones]
Notes:
Strontium-90 is a “bone seeker” that exhibits biochemical behaviour similar to calcium, the next lighter Group 2 element. After entering the organism, most often by ingestion with contaminated food or water, about 70–80% of the dose gets excreted. Virtually all remaining strontium-90 is deposited in bones and bone marrow, with the remaining 1% remaining in blood and soft tissues. Its presence in bones can cause bone cancer, cancer of nearby tissues, and leukaemia. (wikipedia)
6. Which among the following will be the consequence of destruction of all beta cells in the pancreas?
[A] Glucagon secretion will stop and blood glucose levels will increase
[B] Glucagon secretion will stop and blood glucose levels will decrease
[C] Glucagon secretion will stop and digestive enzymes will be secreted
[D] Insulin secretion will stop and blood glucose levels will increase
Show Answer
Correct Answer: D [ Insulin secretion will stop and blood glucose levels will increase]
Notes:
Beta cells secrete insulin. Destruction of beta cells in the pancreas will halt the production of insulin. Therefore, eliminate answer choices (A), (B) and (C). This will lead to an increase in blood glucose levels.
7. Which process develops new species from the existing species?
[A] Homologous
[B] Analogous
[C] Speciation
[D] Genetic variation
Show Answer
Correct Answer: C [Speciation]
Notes:
Speciation is the formation of new species. Speciation is the evolutionary process by which populations evolve to become distinct species. The biologist Orator F. Cook coined the term in 1906 for cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within lineages.
8. Which among the following acts as a resistance against disease in the body? (UPSC Prelims 1982)
[A] Vitamins
[B] Carbohydrates
[C] Red Corpuscles
[D] White Corpuscles
Show Answer
Correct Answer: D [White Corpuscles]
Notes:
White blood cells help you fight infection. When one gets sick, white blood cell count is higher than normal. This is because your body is releasing more of these cells to fight the infection.
9. Which of the following represent Dinosaurs? (UPSC Prelims 1989)
[A] A reptile
[B] An amphibian
[C] A mammal
[D] A bird
Show Answer
Correct Answer: A [A reptile]
Notes:
Dinosaurs were warm-blooded reptiles. Mammal bone study sheds light on dinosaur physiology.
10. Which one among the following is not a good source of nutritional calcium? (UPSC Prelims 2006)
[A] Rice
[B] Ragi
[C] Skimmed milk
[D] Egg
Show Answer
Correct Answer: B [Ragi]
Notes:
Ragi contains only 344 mg of calcium and in 100 gm of ragi protein is 7.3 gm., fat 1.3 gm, fibre 3.6 gms, carbohydrates 72 gms, moisture 13.1 gm.
