81.

Which one of the following is categorised as a parasite in the true sense?

• Human foetus developing inside the uterus draws nourishment from the mother

• Head louse living on the human scalp as well as laying eggs on human hair

• The cuckoo (koel) lays its eggs in crow's nest

• The cuckoo (koel) lays its eggs in crow's nest

At which stage of HIV infection does one usually shows symptoms of AIDS?

• When viral DNA is produced by reverse transcriptase

• When HIV replicates rapidly in helper T- lymphocytes and damages large number of these

• With 15 days of sexual contact with an infected person

• With 15 days of sexual contact with an infected person

Which one of the following statements in wrong in case Bhopal gas tragedy?

• Thousands of human beings died

• Radioactive fallout engulfed Bhopal

• It took place on the night of December 2/3, 1984

• It took place on the night of December 2/3, 1984

Eutrophication is often seen in 

• fresh water lakes

• Ocean

• Mountains

• Mountains

Which one of the following also acts as a catalyst in a bacterial cell?

• sn RNA

• hn RNA

• 23 S rRNA

• 23 S rRNA

What was the most significant trend in the evolution of modern man (Homo sapiens) from his ancestors? 

• shortening of jaws

• Binocular vision

• Increasing brain capacity 

• Increasing brain capacity 

Mutations can be induced with

• IAA

• ethylene

• gamma radiations

• gamma radiations

Wind pollination is common in 

• lilies

• grasses

• orchids

• orchids

'Himgiri' developed by hybridization and selection for disease resistance against rust pathogens is a variety of

• Maize

• sugarcane

• wheat

• wheat

Which one of the following acts as a physiological barrier to the entry of microorganisms in the human body? 

• Tears

• Monocytes

• Skin

• Skin