Question

Land and water dwelling plants, may suffer from
A. Ultraviolet radiation
B. Pollution
C. Air pollution
D. Pollutants

Answer 1

Hint: Land and water dwelling plants depend on atmospheric oxygen and sunlight. Land dwelling plants obtain water and nutrition from soil whereas in water dwelling plants the roots hang in the water.

Complete Answer:
- The plants dwelling in land have much more access to sunlight and other nutrients. The leaves are adapted for transpiration. They have roots which go deep inside the soil and absorb nutrition. Their stem is woody and erect.
- The plants dwelling in water do not have much access to sunlight and oxygen. Rather they use dissolved oxygen present in water. The leaves and stem are spongier which allows them to float in water. The roots are hanging and free floating.
- The major treat to this plant is the ultraviolet radiations. The soil and water absorb most of the UV radiations.
- Pollution is adding unwanted particles to air, water soil etc. It affects the flora and fauna.
- Air pollution: It is the addition of unwanted particles in the air. It majorly affects the health of plants and animals. It can be controlled to some extent.
- Pollutants: Unwanted substances which cause pollution are called pollutants.

The correct answer is (A).

Note: An ultraviolet radiation causes loss of pigmentation in plants. UV-B can cause impairment of photosynthesis in plants. It damages DNA, protein and lipids in the plant which result in death of the plant.