Discuss briefly the role nucleolus in the cell actively involved in protein synthesis.

2

(a)

What are histones? What are their functions?

2

(a)

Multicellular organisms have division of labour. Explain.

2

(a)

The genomic content of the nucleus is constant for a given species whereas, the extra chromosomal DNA is found to be variable among the members of a population. Explain.

2

(a)

Briefly give the contributions of the following scientists in formulating the cell theory.
(i) Rudolf Virchow
(ii) Schleiden and Schwarm

2

(a)