Tissues — Science STD 9 — Question

Signs of eutrophication of water bodies include:

1. Reduced oxygen demand.
2. Rapid decomposition of organic matter.
3. Algal bloom.
4. Fluorosis.

Describe the causes and effects of air pollution.

Common cold is a:

1. Acute disease.
2. Chronic disease.
3. Congenital disease.
4. Genetic disorder.