12.
Match List-I (Pollutants) with List-II (Sources) and select the correct answer:
List-I List-II
a. Petroleum and industrial hydrocarbons 1. Vehicles
b. Airborne lead 2. Offshore wells, oil tankers, industrial wastes
c. Mercury 3. Plastic industries
d. Polychlorinated biphenols 4. Industrial operations

13.
Which of the following diseases is externally seed borne and perennates through the smut spores which adhere to the healthy grains during threshing time?

15.
An action spectrum for the effectiveness of different wave lengths of light demonstrates that the most efficient wave lengths for inhibition of flowering are found between

18.
Who among the following defines root pressure "as a pressure developing in the tracheary elements of the xylem as a result of the metabolic activities of roots"?

19.
When the escape of water takes place from the tips or margins of the uninjured leaves in the vicinity of the mid veins or veinlets, it is called

20.
The complete conversion of glucose, in the presence of oxygen, into carbon dioxide and water with release of energy is called