Out of A-T, G-C pairing, bases of DNA may exist in alternate valency state owing to arrangement called

• tautomerisational mutation

• analogue substitution

• point mutation

• frameshift mutation

Molecular scissors, which cut DNA at specific site is

• pectinase

• polymerase

• restriction endonuclease

• ligase

73.

SO₂ pollution is indicated by

• Desmodium (grasses)

• Sphagnum (mosses)

• Usnea (lichens)

• Cucurbita (climbers)

Sporopollenin is chemically

• homopolysaccharide

• fatty substance

• protein

• heteropolysaccharide

During replication of DNA, Okazaki fragments are formed in the direction of

• 3' ➔ 5'

• 5' ➔ 3'

• 5'➔5'

• 3' ➔ 3'

The chemical nature of chromatin is as follows

• nucleic acids

• nucleic acid and histone proteins

• nucleic acids, histone and non-histone proteins

• nucleic acids and non-histone proteins

Scirpophage incertulus is an example of

• monophagus pest

• diphagus pest

• oligophagus pest

• polyphagus pest

Which one of the following ancestors of man first time showed bipedal movement

• Australopithecus

• Cro-magnon

• Java ape man

• Peking mann

Trophic levels in ecosystem is formed by

• only bacteria

• only plants

• only herbivores

• organisms linked in food chain

The life span of honey bee drone is

• 3-4 months

• 1-2 months

• 6-7 months

• 10-12 months