11. Guinea pigs used in medical research belong to which of the following categories? (UPSC Prelims 1989)
[A] Rodents
[B] Black swine
[C] Stocky and brown in colour
[D] Found in Asia only
Show Answer
Correct Answer: A [Rodents]
Notes:
The guinea pig or domestic guinea pig also known as cavy or domestic cavy, is a species of rodent belonging to the family Caviidae and the genus Cavia.
12. The cyclical fever of malaria is closely associated with which of the following events? (UPSC Prelims 1991)
[A] Immediately after mosquito bite
[B] Upon disintegration and bursting of red blood cells
[C] When the malaria causing germs reach the liver
[D] Release of bacterial toxins into the blood
Show Answer
Correct Answer: B [Upon disintegration and bursting of red blood cells]
Notes:
Rupture of infected red blood cells releases malaria parasites and parasitic material, triggering inflammatory responses associated with fever. Malaria is caused by Plasmodium parasites, not bacteria, and fever does not begin immediately after the mosquito bite.
13. Which one of the following vitamins is considered to be a hormone? (UPSC Prelims 1994)
[A] A
[B] B
[C] C
[D] D
Show Answer
Correct Answer: D [D]
Notes:
Vitamin D is a precursor of calcitriol, its active hormonal form. After activation in the liver and chiefly the kidneys, calcitriol helps regulate calcium and phosphate balance. Cholecalciferol, ergocalciferol, calcidiol and calcitriol are related forms or metabolites, not interchangeable names for one substance.
14. Which one of the following is a modified stem? (UPSC Prelims 1996)
[A] Carrot
[B] Sweet Potato
[C] Coconut
[D] Potato
Show Answer
Correct Answer: D [Potato]
Notes:
The potato tuber is a modified underground stem. Its eyes are buds associated with nodes and can give rise to shoots. Carrot and sweet potato are storage roots; coconut is a fruit.
15. Seed germination takes place in which of the following layers of soil profile?
[A] Organic layer
[B] Surface/A layer
[C] B layer
[D] C layer
Show Answer
Correct Answer: B [Surface/A layer]
Notes:
Surface layer/ A layer which is rich in humus content is responsible for seed germination. Living organisms which aids the production (such as earthworms) also are present in this layer.
16. Which vitamin is also called as ascorbic acid?
[A] Vitamin A
[B] Vitamin C
[C] Vitamin D
[D] Vitamin K
Show Answer
Correct Answer: B [Vitamin C]
Notes:
Vitamin C is also called as ascorbic acid. Deficiency in vitamin C leads to scurvy. Chemical formula of vitamin C is C6H8O6.
17. How may cultivated species contribute to food production globally?
[A] 200
[B] 400
[C] 1000
[D] 900
Show Answer
Correct Answer: A [200]
Notes:
According to FAO’s report “The State of the World’s Biodiversity for Food and Agriculture”, of more than 6,000 plant species cultivated for food production, fewer than 200 contribute significantly to food production globally, regionally or nationally. Only 9 plant species account for almost two-thirds of total crop production.
18. The branch of science that deals with the study of the mental faculties of the brain including emotions is known as__?
[A] Phenology
[B] Phycology
[C] Phrenology
[D] Proctology
Show Answer
Correct Answer: C [Phrenology]
Notes:
The branch of science that deals with the study of the mental faculties of the brain including emotions is known as Phrenology.
19. Who proposed the model for protein synthesis?
[A] Ostwald Avery
[B] Mclyn McCarthy
[C] Colin Macleod
[D] All of these
Show Answer
Correct Answer: D [All of these]
Notes:
Ostwald Avery, McLean McCarthy and Colin MacLeod proposed a model for the process of protein synthesis with the help of DNA in bacterial cells. Cell growth, synthesis of DNA, synapsis and synthesis of proteins.
20. What is the basic unit of Classification?
[A] Genus
[B] Species
[C] Order
[D] Family
Show Answer
Correct Answer: B [Species]
Notes:
Species is the basic unit of classification. Species are known as the basic units of classification because individuals of species are closely related structurally and functionally and can interbreed freely.
