31.

Which one of the following pairs of geographical areas show maximum biodiversity in our country?

• Sunderbans and Rann of Kutch

• Eastern Ghats and West Bengal

• Eastern Himalaya and Western Ghats

• Kerala and Punjab

Genetic diversity in agricultural crops is threatened by

• introduction of high yielding varieties

• intensive use of fertilizers

• extensive intercropping

• intensive use of biopesticides

One of the ex situ conservation methods for endangered species is

• wildlife sanctuaries

• biosphere reserves

• cryopreservation

• national parks

A young drug addict used to show symptoms of depressed brain activity, feeling of calmness, relaxation and drowsiness. Possibly he was taking

• amphetamine

• marijuna

• pethidine

• valium

Antigen binding site in an antibody is found between

• two light chains

• two heavy chains

• one heavy and one light chain

• either between two light chains or between one heavy and one light chain depending upon the nature of antigen

Which one of the following events is correctly matched with the time period in a normal menstrual cycle?

• Release of egg: 5^th day

• Endometrium regenerates: 5 - 10 days

• Endometrium secretes nutrients for implantation : 11 - 18 days

• Rise in progesterone level : 1 - 15 days

A tumor inducing plasmid widely used in the production of transgenic plants is that of

• Escherichia coli

• Bacillus thuringiensis

• Staphylococcus aureus

• Agrobacterium tumefaciens

Which one of the following statement pertaining to pollutants is correct?

• DDT is a non-biodegradable pollutant

• Excess fluoride in drinking water causes osteoporosis

• Excess cadmium in drinking water causes black foot disease

• Methylmercury in water may cause "Itai ltai" disease

The "cri-du-chat" syndrome is caused by change in chromosome structure involving

• deletion

• duplication

• inversion

• translocation

Grain colour in wheat is determined by three pairs of polygenes. Following the cross AABBCC (dark colour) x aabbcc (light colour), in F₂ generation what proportion of the progeny is likely to resemble either parent?

• None

• Less than 5 percent

• One third

• Half