(a)(i) Explain briefly the cell theory.
(ii) Name two scientists who contributed to the development of the cell theory.

(b) Make a large labelled diagram of a typical plant cell.

(c) List three ways in which a typical plant cell differs from a typical animal cell.

(d) State one difference each between Hydra and the mammals with respect to:
(i) level of organisation; (ii) symmetry; (iii) number of body layers.