1. Phenomenon when organisms resemblingothers for escaping from enemies is (1988)(a) adaptation (b) mimicry(c) homology (d) analogy

2. Employment of hereditary principles in theimprovement of human race is (1990)

(a) Euthenics (b) Eugenics(c) Euphenics (d) Ethnology

3. Homeostasis is (1991)

(a) tendency to change with change inenvironment

(b) tendency to resist change(c) disturbance in regulatory control(d) plants and animals extracts used in

homeopathy

4. Pedology is science of (1991)

(a) earth (b) soil(c) diseases (d) pollution

5. Study of fossils is (1991)

(a) Palaeontology (b) Herpetology(c) Saurology (d) Organic evolution

6. A nucleotide is formed of (1991)

(a) purine, pyrimidine and phosphate(b) purine, sugar and phosphate(c) nitrogen base, sugar and phosphate(d) pyrimidine, sugar and phosphate

7. Glycogen is a polymer of (1992)

(a) galactose (b) glucose(c) fructose (d) sucrose

8. Adenine is (1992)

(a) purine (b) pyrimidine(c) nucleoside (d) nucleotide

9. In RNA, thymine is replaced by (1992)

(a) adenine (b) guanine(c) cytosine (d) uracil

10. The CO2 content by volume, in the atmospheric air is about (1997)

(a) 0.0314% (b) 0.34%(c) 3.34% (d) 4%

11. Which one of the following is a living fossil?(1997)

(a) Pinus longifolia (b) Dalbergia sissoo(c) Mirabilis (d) Ginkgo biloba

12. Warm ocean surge of the Peru Currentrecurring every 5–8 year or so in the EastPacific of South America is widely known as

(a) Gulf Stream (b) El Nino (1998)(c) Aye Aye (d) Magnox

13. If there was no CO2 in the earth’s atmospherethe temperature of earth’s surface would be(a) higher than the present (1998)

(b) less than the present(c) the same(d) dependent on the amount of oxygen in the

atmosphere

14. An orchid resembling the female of an insect soas to be able to get pollinated is due tophenomenon of (1998)(a) mimicry(b) pseudocopulation(c) pseudopollination(d) pseudoparthenocarpy

15. The most important feature of all livingsystems is to (2000)(a) utilize oxygen to generate energy(b) replicate the genetic information(c) produce gametes(d) utilize solar energy for metabolic activities

16. Relative Biological Effectiveness (RBE) isusually referred to damages caused by (2000)

(a) low temperature (b) high temperature(c) encephalitis (d) radiation

17. First life on earth was (2001)

(a) cyanobacteria(b) chemoheterotrophs(c) autotrophs(d) photoautotrophs

18. What is true for photolithotrophs? (2001)

(a) Obtain energy from radiations andhydrogen from organic compounds

(b) Obtain energy from radiations andhydrogen from inorganic compounds

(c) Obtain energy from organic compounds(d) Obtain energy from inorganic compounds

19. Most abundant organic compound on earth is (a) protein (b) cellulose (2001)(c) lipids (d) steroids

The Living World

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The Living World

20. Reason of diversity in living being is (2001)

(a) mutation(b) gradual change(c) long term evolutionary change(d) short term evolutionary change

21. Organisms which obtain energy by theoxidation of reduced inorganic compounds arecalled (2002(a) photoautotrophs(b) chemoautotrophs(c) saprozoic(d) coproheterotrophs

22. There is no life on moon due to the absence of(a) O2 (b) water (2002)(c) light (d) temperature

23. Which one of the following is categorisedunder living fossils? (2003, 04)

(a) Selaginella (b) Pinus(c) Cycas (d) Metasequoia

24. According to Oparin, which one of thefollowing was not present in the primitiveatmosphere of the earth? (2004)(a) Methane(b) Oxygen(c) Hydrogen(d) Water vapour

25. Age of fossils in the past was generallydetermined by radio-carbon method and othermethods involving radioactive elements foundin the rocks. More precise methods, whichwere used recently and led to the revision ofthe evolutionary periods for different groups oforganisms, include

(2004)

(a) study of carbohydrates/proteins in fossils(b) study of the conditions of fossilization(c) Electron Spin Resonance (ESR) and fossil

DNA(d) study of carbohydrates/proteins in rocks

26. More than 70% of world’s fresh water iscontained in (2005)(a) Antarctica(b) Greenland(c) Glaciers and Mountains(d) Polar ice

27. Barophilic prokaryotes (2005)

(a) grow slowly in highly alkaline frozen lakesat high altitudes

(b) occur in water containing highconcentrations of barium hydroxide

(c) grow and multiply in very deep marinesediments

(d) readily grown and divides in sea waterenriched in any soluble salt of barium

28. Carbohydrates the most abundantbiomolecules on earth, are produced by (2005)

(a) all bacteria, fungi and algae(b) fungi, algae and green plant cells(c) some bacteria, algae and green plant cells(d) viruses, fungi and bacteria

29. Which of the following is the relatively mostaccurate method for dating of fossils? (2005)(a) Radio-carbon method(b) Potassium-argon method(c) Electron-spin resonance method(d) Uranium-lead method

30. Animals have the innate ability to escape frompredation. Examples for the same are givenbelow. Select the incorrect example. (2005)

(a) Colour change in Chameleon(b) Enlargement of body size by swallowing

air in puffer fish(c) Poison fangs in snakes(d) Melanism in moths

31. Praying mantis is a good example of (2006)

(a) warning colouration(b) social insects(c) camouflage(d) Mullerian mimicry

32. Which one of the following is not a living fossil?(a) King crab (b) Sphenodon (2006)

(c) Archaeopteryx (d) Peripatus

33. Which one of the following is an example ofnegative feedback loop in humans? (2007)

(a) Constriction of skin blood vessels andcontraction of skeletal muscles when it istoo cold

(b) Secretion of tears after falling of sandparticles into the eye

(c) Salivation of mouth at the sight ofdelicious food

(d) Secretion of sweat glands and constrictionof skin blood vessels when it is too hot

34. The living organisms can be unexceptionallydistinguished from the non-living things on thebasis of their ability for (2007)

(a) responsiveness to touch(b) interaction with the environment and

progressive evolution(c) reproduction(d) growth and movement

35. Biological organization starts with (2007)

(a) submicroscopic molecular level

(b) cellular level

(c) organismic level

(d) atomic level

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The Living World

36. Which one of the following scientist’s name iscorrectly matched with the theory put forth byhim? (2008)

(a) Weismann —Theory of continuity of Germplasm

(b) Pasteur — Inheritance of acquired characters

(c) de Vries — Natural selection(d) Mendel — Theory of pangenesis

1. Mimicry is the phenomenon of resemblance ofone species with another. It is a means ofadaptation and protection against predation.The species which is copied is called a model,while the animal which copies other is knownas mimic, eg, viceroy butterfly mimics toxicmonarch butterfly.

2. Eugenics refers to improvement of human raceby modifying fertility or employing thehereditary principles.

3. Homeostasis (Gr. homeos = similar; stasis =standing) is the tendency of maintaining arelatively stable internal physiologicalenvironment in an organism, or steady-stateequilibrium in a population or ecosystem. It iscarried out by regulatory mechanisms whichcoordinate internal functions such as providing nutrients to cells and transporting substances.

4. Pedology is the study of soil and soil properties.

5. Palaeontology is the study of fossils (remains or impressions of ancient forms) and theirdistribution in rocks of various ages. Study ofanimal fossils is known as Palaeozoology andstudy of plant fossils is known as Palaeobotany.

6. Nucleotide is the basic unit of nucleic acids(DNA and RNA). It is composed of nucleoside(nitrogenous base + pentose sugar) andphosphate group.

7. Glycogen is a storage carbohydrate(a polysaccharide of α-glucose) of animals andfungi. Glycogen is stored in liver and muscles in

human body. It is hydrolysed to form glucose(glycogenolysis).

8. Purines are 9-membered double ring nitrogenbases which possess nitrogen at 1, 3, 7 and 9positions, eg, Adenine (A), Guanine (G).

9. DNA consists of nitrogenous bases, adenine,guanine, cytosine and thymine, whereas inRNA thymine is replaced by uracil. The othernitrogenous bases, ie, adenine, guanine,cytosine are present both in RNA and DNA.

10. CO2 constitutes 0.0314% of the atmosphere.Producers use CO2 alongwith energy from sunand make carbon compounds such as glucoseduring the process of photosynthesis.Consumers use these compounds as energysource.

11. Ginkgo biloba is believed to be the oldest livingseed plant. Its fossils have been found in rocksas old as Triassic. It still survives with littlechange over this long period of time whileother members of its group have becomeextinct.

12. El Nino is a warm ocean surge of Peru Current(flowing North from Antarctic along the Westcoast of South America to South Ecuador, theWest). It recurs every 5-8 year or so in theEast Pacific of South America.

13. CO2 layer around the earth surface acts asinsulator and does not allow heat of the earthto escape into space thus keeping the earthwarm.

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Answers

1. (b) 2. (b) 3. (b) 4. (b) 5. (a) 6. (c) 7. (b) 8. (a)

9. (d) 10. (a) 11. (d) 12. (b) 13. (b) 14. (b) 15. (b) 16. (d)

17. (b) 18. (b) 19. (b) 20. (c) 21. (b) 22. (b) 23. (c) 24. (b)

25. (c) 26. (d) 27. (c) 28. (c) 29. (c) 30. (c) 31. (b) 32. (c)

33. (a) 34. (c) 35. (a) 36. (a)

Hints & Solutions

14. For its pollination the orchid Ophrys speculumhas picked on the most selective attraction inthe entire animal kingdom. It is pollinated by ahairy wasp, Colpa aurea. The wasp has a fixedhabit whereby its males leave the burrows forabove ground existence about four weeksbefore the females emerge for the open-airmating. The orchid opens its flowers about thesame time the males appear and they possessan appearance and odour similar to thosepossessed by the female wasps. Theinexperienced males mistake the Ophrysflowers for their female counterparts and landto perform the act of pseudocopulation. Theinsect repeats the act with a number of orchidflowers and carries pollinia from one flower toanother. This insect-plant relationship isbeneficial only to the plant.

15. Reproduction is necessary for continuity of life. However, production of gametes is not onlymethod for this. A number of organismsreproduce asexually. In any case, cell divisionis necessary which involves replication of DNA.

16. RBE (Relative Biological Effectiveness) is acomparison of the dose of the radiation beingstudied with the dose of standard radiationproducing the same effect.

17. First living beings were formed in theenvironment of sea having abundant organicmolecules. They absorbed the organicmaterials for the sake of nutrition and hence,were chemoheterotrophs.

18. Photolithotrophs used light as energy andinorganic electron donor (like H , H S2 2 ) ashydrogen source. Purple and green sulphurbacteria are examples of photolithotrophs.

19. Cellulose, constituting the cell wall of plants, ismost abundant organic molecule on earth.

20. Though mutation provides the source ofvariation, the diversity in living beings is due to natural selection of variations and consequentevolutionary change over a long periods oftime.

21. The organisms obtaining energy by chemicalreactions independent of light are calledchemotrophs. The reductants obtained fromthe environment may be inorganic (in case ofchemoautotrophs) or organic (in case ofchemoheterotrophs).

Photoautotrophs: Organisms that make theirown food by photosynthesis, using the lightenergy.

Saprozoic: Organisms which obtain food fromdead and decaying matter.

22. Water is an essential constituent of cytoplasmof all living organisms. It helps in distributionof substances within the organism, eliminationof waste products, body temperaturemaintenance etc. It is absent on moon.

Anaerobic organisms can live in the absence of O2. Light and temperature are already knownto exist on moon.

23. Order—Cycadales includes both living andfossil members which are originated in theupper Triassic period of the early Mesozoic era.

The family—Cycadaceae of this order has 10living and one fossil genera. Cycas comes under living genera and has a long writing history so,is also known as living fossil.

24. According to Oparin, the atmosphere ofprimitive earth was reducing because H atomswere most numerous and most reactive. Largequantities of H , N2 2, water vapour, CO2, CH4

and NH3 were present but free oxygen was notpresent in significant amount.

25. Electron Spin Resonance (ESR) measuresnumber of charges occupying deep traps incrystal band gap. The basic principle of ESR issame as those for luminescence, ie, electronsbecome trapped and stored as a result ofionising radiations, eg, dating of tooth enamel.

26. Three fourth surface of earth (about 71% oftotal) is occupied by oceans which contain97.5% of total water. This is marine water withabout 3.5% salt contents. Rest water, ie, 2.5%is fresh water which occurs on land. Mostamount of this water (about 1.97%) occurs asFrozen ice caps and Glaciers and 0.5% freshwater occurs as ground water.

27. Barophilic prokaryotes grow and multiply invery deep marine sediments.

28. Some photosynthetic bacteria such asRhodopseudomonas can prepare carbohydrates. But during this type of food synthesis O2 doesnot evolved because in this case hydrogendonor is other than H O2 . Algae (green andblue-green) and all green plant cells preparetheir food (carbohydrate) throughphotosynthesis. Here, hydrogen ions aredonated by water molecules by the process ofphotolysis of water, ie, O2 is released duringthis type of food synthesis.

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29. Electron spin resonance method is the mostaccurate method for dating of fossils.

30. Animals resist predation by cryptic colouration, deceptive marking, behavioural defences andthe possession of mechanical or chemicaldefences.

Example :

(a) Enlargement of body size by swallowingair in puffer fish.

(b) Melanism in moths.(c) Colour change in Chameleon.

31. Praying mantis (Mantis religiosa) is a largesocial insect. It has small triangular head, along prothorax and abdomen consisting of 10segments. The wings are well developed andthe pincer-like forelegs are modified forgrasping prey. It usually inhabits plantationareas. It destroys certain harmful insects, so itis useful.

32. Archaeopteryx lithographica is not a livingfossil. It is a fossil bird that lived in Jurassicperiod about 180 million years ago. Its fossildisplays the characters of both reptiles(eg, long tail, bones not pneumatic, jaws withteeth, fingers terminating into claw, presenceof weak sternum, free caudal vertebra etc) andbirds (eg, presence of feathers, jaws modified

into beak, fore limbs modified into wings,intimate fusion of skull bones etc). King crab,Sphenodon and Peripatus are the living fossils.

33. Skin blood vessels constrict and skeletalmuscles contract due to cold is an example ofnegative feedback mechanism of homeostasis.

34. All living things reproduce passing on traitsfrom one generation to next. Non-living thingscannot reproduce.

35. Biological organization starts withsubmicroscopic molecular level, where fourtypes of molecules, ie, carbohydrates, lipids,proteins and nucleic acids are organized intoorganelles of cell.

36. Scientist Theory

Pasteur — Germ theory of disease

Charles Darwin — Theory of natural

selection

Lamarck — Inheritance of acquired

characters

Weismann — Theory of continuity of

germplasm

Hugo de Vries — Mutation theory

Mendel — Laws of inheritance

Darwin — Theory of pangenesis.

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