11. Which of the following is the main constituent of the Gobar gas? (UPSC Prelims 1979).
[A] Carbon dioxide
[B] Methane
[C] Ethylene
[D] Carbon monoxide
Show Answer
Correct Answer: B [Methane]
Notes:
Biogas or Gobar gas is produced by the breakdown of organic matter in the absence of oxygen. It can be produced from raw materials such as agricultural waste, manure, municipal waste, plant material, sewage, green waste or food waste. It is a renewable energy source. It comprises primarily methane (CH4) and carbon dioxide (CO2) and may have small amounts of hydrogen sulphide (H2S), moisture and siloxanes. It is produced by anaerobic digestion.
12. BCG vaccination is to be given to a new born child after what time? (UPSC Prelims 1979).
[A] Immediately after birth
[B] Within 48 hours
[C] Within seven days
[D] Within six months
Show Answer
Correct Answer: A [Immediately after birth]
Notes:
Bacillus Calmette Guérin or BCG is usually given around birth to prevent severe TB in infants. The neonatal immune system is immature. Delaying BCG vaccination from birth to 10 weeks of age would enhance the vaccine-induced immune response. The BCG vaccine is an injection given to children who have a higher risk of catching TB. The BCG vaccine helps your child’s immune system fight the germs that cause TB and helps stop them from getting serious TB disease.
13. Which of the following clearly defines the meaning of Plankton? (UPSC Prelims 1982)
[A] A kind of fish
[B] A submerged platform in waters
[C] Drifting of organisms in a body of water
[D] A kind of animal living under water
Show Answer
Correct Answer: C [Drifting of organisms in a body of water]
Notes:
Planktons are very small plants and animals that float on the surface of the sea and on which other sea animals feed.
14. Which of the following clearly define Pyrilla? (UPSC Prelims 1991)
[A] Disease of teeth and gums
[B] An insect pest
[C] A character of ancient Greek mythology
[D] A building heated by solar energy
Show Answer
Correct Answer: B [An insect pest]
Notes:
Adult Pyrilla perpusilla is a pale tawny-yellow, soft-bodied insect with head prominently drawn forward to form a snout. Both adults and nymphs are very active and suck sap from the leaves of sugarcane. On the slightest disturbance, they jump from leaf to leaf.
15. Consider the following conditions of sick human body
1. Swollen lymph nodes
2. Sweating at night
3. Loss of memory
4. Loss of weight
Which of these are the symptoms of AIDS? (UPSC Prelims 2003)
[A] 1 and 2
[B] 2, 3 and 4
[C] 1, 2 and 3
[D] 1, 2, 3 and 4
Show Answer
Correct Answer: D [1, 2, 3 and 4]
Notes:
AIDS is a viral disease. In this disease the immune system weakens and the body becomes prone to different type of infection by pathogens. Sweating at night, swollen lymph nodes, loss of memory and loss of weight are also symptoms of AIDS.
16. Which among the following is not a fat soluble vitamin?
[A] Vitamin A
[B] Vitamin B
[C] Vitamin K
[D] Vitamin D
Show Answer
Correct Answer: B [Vitamin B]
Notes:
Vitamins are classified into two broad categories, water soluble (vitamins B complex and C) and fat soluble (vitamins A,D,E and K).
Extra info: Excess intake of fat soluble vitamins leads to toxicity and poses greater risk.
17. Which branch of biology is deal with the study of seeds?
[A] Embryology
[B] Spermatology
[C] Gerontology
[D] Histology
Show Answer
Correct Answer: B [Spermatology]
Notes:
The study of seeds is known as spermatology. It involves the study in terms of morphology, characteristics and interactions with the environment.
18. Robert Hooke is known for which of the following works?
[A] how messages pass between nerve cells in mammals
[B] first use of the word cell
[C] theory of punctuated equilibrium
[D] aquatic ape theory
Show Answer
Correct Answer: B [first use of the word cell]
Notes:
Robert Hooke is known for his discovery of the law of elasticity (Hooke’s law), for his first use of the word cell in the sense of a basic unit of organisms, and for his studies of microscopic fossils, which made him an early proponent of a theory of evolution.
19.
Who among the following is considered to be the father of Comparative Anatomy?
[A] Georges Cuvier
[B] Stephen Hales
[C] Hugo de Vries
[D] Edwin John Butler
Show Answer
Correct Answer: A [Georges Cuvier]
Notes:
Georges Cuvier is considered to be the father of Comparative Anatomy.
20. Which of the following causes chloroplasts to be green?
[A] because they contain the pigment cobalt
[B] because they contain the pigment chlorophyll
[C] because they contain the pigment carotenoids
[D] because they contain the pigment betacyanins
Show Answer
Correct Answer: B [because they contain the pigment chlorophyll]
Notes:
Chloroplasts are green because they contain the pigment chlorophyll, which is important for photosynthesis. Chlorophyll occurs in many different forms. Chlorophyll a and b are the major pigments of higher plants and green algae.