Explain how IVF as a technique helped childless couples in having children .

Explain IVF and ET?

List some methods to assist infertile couples to have children.

Explain how friction helps in walking.

Explain cytokinesis with the help of sketches only.

One of the main objectives of biotechnology is to minimize the use of insecticides on cultivated crops. Explain help of a suitable example how insect resistant crops have been developed using techniques of biotechnology.

Briefly explain the IVF and ET. What are the conditions in which these methods are advised?