11. Which of the following are the postulates of Darwin’s theory of evolution?
[A] Within any population, there is natural variation.
[B] Even though all species produce a large number of offsprings, populations remain fairly constant
[C] The struggle for survival within populations eliminates the unfit individuals.
[D] All the above are correct
Show Answer
Correct Answer: D [All the above are correct]
Notes:
Darwin’s theory of evolution can be described as: within any population, there is natural variation. Some individuals have more favourable variations than others. Even though all species produce a large number of offsprings, populations remain fairly constant naturally. The struggle for survival within populations eliminates the unfit individuals. This is called natural selection.
12. Which of the following is the result of the decrease in white blood cells? (UPSC Prelims 1979).
[A] Decrease in Antibodies
[B] Increase in Antigens
[C] Increase in Antibodies
[D] No change
Show Answer
Correct Answer: A [Decrease in Antibodies]
Notes:
A low white blood cell count usually is followed by decrease in number of antibodies. When your white blood cell count is low you may not have the usual signs and symptoms when developing an infection such as Redness, Swelling, Pus formation, Cough, Sputum, Nasal drainage and decrease in antibodies.
13. ‘Lathyrism’ is a crippling disease caused by eating which of the following? (UPSC Prelims 1989)
[A] Tinned fish
[B] Chick pea and pulses
[C] Meat
[D] Adulterated oil
Show Answer
Correct Answer: B [Chick pea and pulses]
Notes:
The lathyrism resulting from the ingestion of Lathyrus odoratus seeds (Chick pea and pulses) is often referred to as odoratism or osteolathyrism, which is caused by a different toxin (beta-aminopropionitrile) that affects the linking of collagen, a protein of connective tissues.
14. Endoscopy, a technique used to explore the stomach or other inner parts of the body is based on the which of the following phenomenon? (UPSC Prelims 1999)
[A] Total internal reflection
[B] interference
[C] diffraction
[D] polarisation
Show Answer
Correct Answer: A [Total internal reflection]
Notes:
Endoscopy, a technique used to explore the stomach or other inner parts of the body is based on total internal reflection. The endoscopy procedure uses an endoscope to examine the interior of a hollow organ or cavity of the body. Unlike many other medical imaging techniques, endoscopes are inserted directly into the organ. There are many types of endoscopes.
15. What term is used for a gene that exhibits multiple effects?
[A] Pleiotropism
[B] Multitropism
[C] Complementary
[D] Allele
Show Answer
Correct Answer: A [Pleiotropism]
Notes:
Pleiotropism describes the genetic effect of a single gene on multiple phenotypic traits. A classic example of pleiotropy is phenylketonuria, a human disease that affects multiple systems but is caused by one gene defect. The underlying mechanism is that the gene codes for a product that is, for example, used by various cells, or has a signaling function on various targets.
16. Which among the following is not a part of Vitamin B complex?
[A] Vitamin B2
[B] Vitamin B4
[C] Vitamin B6
[D] Vitamin B12
Show Answer
Correct Answer: B [Vitamin B4]
Notes:
Vitamin B complex consists of 8 vitamins namely B1(Thiamine), B2(Riboflavin), B3(Niacin), B5(Pantothenic acid), B6(Pyridoxine), B7(Biotin), B9(Folate/Folic acid) and B12(Cobalamin).
17. Which of the following is the largest group of the plant kingdom?
[A] Thallophyta
[B] Bryophyta
[C] Pteridophyta
[D] Euglena
Show Answer
Correct Answer: A [Thallophyta]
Notes:
The plant kingdom consists of 390,000 species known till date. The plant kingdom is divided into five major groups: Thallophyta, Bryophyta, Pteridophyta, Gymnosperms and Angiosperms.
18. What type of embryo is most often used for viral assays?
[A] Mouse
[B] Rat
[C] Cat
[D] Chicken
Show Answer
Correct Answer: D [Chicken]
Notes:
Chicken is a type of embryo is most often used for viral assays.
19. Which of the following is not a form of bacteria?
[A] Coccus
[B] Bacillus
[C] Vibrio
[D] Lobosa
Show Answer
Correct Answer: D [Lobosa]
Notes:
Lobosa is a taxonomic group of amoeba in the Amoebozoa genus.
20. Which of the following includes ‘club fungus’ in this fungal division?
[A] Zygomycota
[B] Deuteromycota
[C] Basidiomycota
[D] Ascomycota
Show Answer
Correct Answer: C [Basidiomycota]
Notes:
Basidiomycota is one of the two larger divisions. Together with the Ascomycota, they constitute the subfamily Dicarya within the kingdom Fungi.