How is the process of pollination is different from fertilisation.

Is the chromosome number of the zygote, embryonic cells, and adult of a particular organism always constant? How is the constancy maintained in these three stages?

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.

Name the process of asexual reproduction shown by yeast. What type of living being is yeast? What is its commercial importance?

(a) List three distinguishing features between sexual and asexual types of reproduction.

(b) Explain why variations are observed in the offsprings of sexually reproducing organisms?

List three distinguishing features between sexual and asexual types of reproduction, in tabular form.

Define reproduction. How does it help in providing stability to the population of species?

An element 'X' has mass number 35 and number of neutrons 18. Write atomic number and electronic configuration of 'X'. Also write group number, period number and valency of 'X'.

Why is DNA copying necessary during reproduction?

What are those organisms called which bear both the sex organs in the same individual? Give one example of such organism.