Explain with the help of an example the type of evolution homology is based on.

Explain mutualism with the help of an example.

Explain food chain with the help of one example .

Explain commensalism, with the help of an example.

Explain with the help of suitable example polar covalent bond.

Explain with the help of an example each how the following provide evidences in favour of evolution : (a) Homologous organs (b) Analogous organs (c) Fossils

Explain brood parasitism with the help of an example.

Explain with examples the various types of industries.

With the help of an example, explain how variation leads to evolution.