In 1984, the Bhopal gas tragedy took place because methyl isocyanate:

1. Reacted with ammonia

2. Reacted with CO₂

3. Reacted with water

4. Reacted with DDT

Which one of the following is the correct matching of a vitamin, its nature, and its deficiency disease:

1. Vitamin K– Fat-soluble Beri Beri

2. Vitamin A– Fat-soluble Beri Beri

3. Vitamin K– Water soluble Pellagra

4. Vitamin A– Fat-soluble Night blindness

Photosynthetically active radiation (PAR) represents the following range of wavelengths:
1. 450-950 nm
2. 340-450 nm
3. 400-700 nm
4. 500-600 nm 

The technique of obtaining a large number of plantlets by tissue culture method is called:

1. Organ culture

2. Micropropagation

3. Micropropagation

4. Plantlet culture

The most abundant element present in the plant is:

1. Nitrogen

2. Manganese

3. Iron

4. Carbon 

Cell elongation in internodal regions of the green plants takes place due to:

Diversification in plant life appeared:

A terrestrial animal must be able to: 

1. Conserve water
2. Actively pump salts out, through the skin
3. Excrete large amounts of salts in urine
4. Excrete large amounts of water in urine

Mast cells of connective tissue contain:

1. Heparin and histamine

2. Heparin and calcitonin

3. Serotonin and melanin

4. Vasopressin and relaxin

Uricotelism is found in:

1. Fishes and freshwater protozoans

2. Birds, reptiles, and insects

3. Frogs and toads

4. Mammals and birds