List and explain in brief three methods of contraception.

What is placenta? State its function in human female.

Write one main difference between asexual and sexual mode of reproduction. Which species is likely to have comparatively better chances of survival – the one reproducing asexually or the one reproducing sexually? Give reason to justify your answer.

Draw a neat diagram of a flower showing its various parts. In this diagram mark stem, receptacle, sepals, petals, stamen and carpel.

Draw diagrams to explain the regeneration that takes place in each of the body parts of planaria when its body is cut into three pieces. Name any other organism in which  a similar process can be observed.

Explain the mechanism of sex determination in humans.

Why does menstruation occur?

List any four steps involved in sexual reproduction and write its two advantages.

Draw a diagram of the female reproductive system and explain its various parts.

What changes take place in boys during the reproductive phase?