(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. 
 

(a) Make a labelled diagram to show the internal structure of the mammalian ear.

(b) Describe the mechanism of hearing in mammals.

(c) State two ways of caring for the ear. 
 

(a) (i) List three components of an ecosystem (ii) Describe briefly the interaction among the components named in (a) (i).

(b) List three major steps that are usually taken in studying plants and animals in community.

(c) State the importance of each of the following in a population and explain how each affects the growth of a population:
(i) competition; (ii) pathogens; (iii)water.