(a) Microorganisms can be seen with the help of a microscope.
(b) Blue green algae fix nitrogen directly from air to enhance fertility of soil.
(c) Alcohol is produced with the help of microorganisms.
(d) Cholera is caused by bacteria.

A | B | ||
|---|---|---|---|
| (i) | Bacteria | (a) | Fixing nitrogen |
| (ii) | Rhizobium | (b) | Setting of curd |
| (iii) | Lactobacillus | (c) | Baking of bread |
| (iv) | Yeast | (d) | Causing malaria |
| (v) | A protozoan | (e) | Causing cholera |
| (vi) | A virus | (f) | Causing AIDS |
| (g) | Producing antibodies | ||
