Ans: (a)
337. When a cell neither shrinks nor swells when kept in a fluid, then the fluid in the cell in relation to ambient fluid is called:
[NDA 1990]
(a) Hypertonic
(b) Hypotonic
(c) Isotonic
(d) Hyalotonic
Ans: (c)
338. The study of the relation of animals and plants to their surroundings is called: [Intelligence Bureau 1994]
(a) Ecology
(b) Ethnology
(c) Genealogy
(d) Iconology
Ans: (a)
339. Ants are always seen moving in a line one after another. They trace the path because of the secretion of chemicals
called:
(a) detectors
(b) sex hormones
(c) pheromones
(d) None of the above
Ans: (c)
340. The maximum fixation of solar energy is done by: [Intelligence Bureau 1994]
(a) bacteria
(b) protozoa
(c) fungi
(d) green plants
Ans: (d)
341. Which of the following animals resembles most to human beings in terms of physical and mental capabilities?
(a) Langur
(b) Rhesusmonkey
(c) Gorilla
(d) Chimpanzee
Ans: (d)
342. Which of the following have not undergone much .of a change during the process of evolution over millions of years?
[CDS 1994]
1) Crocodile
2) Cockroach
3) Horse
(a) 1 and 2
(b) 2 and 3
(c) 1 and 3
(d) 1, 2 and 3
Ans: (a)
343. Nitrogen fixation is done by : [IFS 1990]
(a) red algae
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