11. Which of the following is correlated with blood pressure?
[A] Pancreas
[B] Liver
[C] Adrenal
[D] Testis
Show Answer
Correct Answer: C [Adrenal]
Notes:
Pheochromocytoma, a rare, usually benign, tumor of the adrenal glands resulting in the glands secreting excessive amounts of the hormones adrenaline and noradrenaline (catecholamines). This causes variable symptoms such as high blood pressure, sweating, etc.
12. What is the name of a group of similar cells performing a specific function?
[A] Tissue
[B] Organ
[C] Organ system
[D] Cellular organization
Show Answer
Correct Answer: A [Tissue]
Notes:
A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues.
13. Which of the following features of the human immunodeficiency virus (HIV) makes it a living entity? (UPSC Prelims 1990)
[A] Excrete in human serum
[B] Disturb host cell respiration
[C] Undergo auto-reproduction
[D] Move from one cell to another
Show Answer
Correct Answer: C [Undergo auto-reproduction]
Notes:
The human immunodeficiency virus is a type of virus called a retrovirus. Like all viruses, human immunodeficiency virus reproduces using the genetic machinery of the cell it infects. With the help of an enzyme called integrase (also produced by HIV), the viral DNA becomes integrated with the cell’s DNA.
14. The bats are able to fly in dark since their wings produce which of the following waves? (UPSC Prelims 1992)
[A] Infrared rays
[B] Ultrasonic waves
[C] Sound waves
[D] Ultraviolet rays
Show Answer
Correct Answer: B [Ultrasonic waves]
Notes:
Bats can fly in dark because they. Bat echolocation is very much similar to a SONAR and is a perceptual system where ultrasonic sounds are emitted specifically to produce echoes.
15. Camel uses its hump for which of the following purposes? (UPSC Prelims 1993)
[A] Storing water
[B] storing fat
[C] balancing the body during walking in desert sand
[D] temperature regulation
Show Answer
Correct Answer: B [storing fat]
Notes:
A camel’s hump does not hold water at all – it actually stores fat. The camel uses it as nourishment when food is scarce. If a camel uses the fat inside the hump, the hump will become limp and droop down. The hump is not used for water storage, but camels can go for long periods of time without water.
16. When one gene controls two or more different characters simultaneously, the phenomenon is known by which of the following names? (UPSC Prelims 2002)
[A] Apomixis
[B] Pleiotropy
[C] Polyploidy
[D] Polyteny
Show Answer
Correct Answer: B [Pleiotropy]
Notes:
• Polyploidy occurs in cells and organisms when there are more than two paired (homologous) set of chromosome founds which controls more than one characters simultaneously.
• Apomixis is the process of asexual reproduction in which the embryo grows from egg cells without being fertilized.
• Pleiotropy occurs when a single gene influences multiple phenotypic traits.
• Polytene is a giant chromosome found in some two-winged flies.
17. Which among the following is a water soluble vitamin?
[A] Vitamin A
[B] Vitamin C
[C] Vitamin D
[D] Vitamin E
Show Answer
Correct Answer: B [Vitamin C]
Notes:
Except vitamins A, D, E and K, remaining all vitamins are water soluble vitamins. Vitamins A, D, E and K are fat soluble vitamins.
18. Who was the father of DNA Fingerprinting?
[A] James Watson
[B] Hargobind Khurana
[C] Alec Jeffereys
[D] Nirenberg
Show Answer
Correct Answer: C [Alec Jeffereys]
Notes:
In 1984, Alec Jeffreys developed the technique of DNA fingerprinting. These techniques have revolutionised the way that the police solve crimes.
19. What are plants without seeds having vascular tissue?
[A] Gymnosperms
[B] Bryophytes
[C] Angiosperm
[D] Pteridophytes
Show Answer
Correct Answer: D [Pteridophytes]
Notes:
Pteridophyte is a type of vascular plant, which spreads spores. Pteridophytes produce neither flowers nor seeds, they are sometimes referred to as “cryptogams”.
20. What is involved in the release of pollen grains?
[A] Pectin and cellulose
[B] Lignocellulose
[C] Pollenkit
[D] Sporopollenin
Show Answer
Correct Answer: D [Sporopollenin]
Notes:
Sporopollenin is the most chemically inert organic polymer. It is a major component of the tough outer (outer) walls of plant spores and pollen grains.
