Water is very essential for life. List any three features that enable plants and animals to survive in water scarce environment.

OR

(a) What would be the consequence of failure of the electrostatic precipitator of a thermal plant?

(b) Mention any four methods by which vehicular air pollution can be controlled.

In water scarce conditions, both plants and animals have developed specific features which help them to adapt in such conditions.

• Plants –

i. Deep tap roots to absorb water from deep into the soil

ii. Waxy cuticles on leaf surfaces and stomata arranged in deep pits to reduce water loss by transpiration.

iii. Have a special photosynthetic pathway (CAM) that enables their stomata to remain closed during the day

iv. Desert plants like Opuntia, have leaves reduced to spines and the photosynthetic function is taken over by the flattened stems.

• Animals –

i. No sweating

ii. Body covered with scales

iii. deposition of fat in sub epidermal layer

iv. burrowing nature

v. thick skin

OR

(a) Electrostatic precipitator can remove 99% particulate matter present in the exhaust from a thermal power plant. Failure of the electrostatic precipitator will lead to the release of exhaust filled with particulate matter into the air causing air pollution.

(b) Vehicular air pollution can be controlled by –

i. Use of CNG

ii. Use of catalytic converters

iii. Phasing out of old vehicles

iv. Use of low sulphur fuel