Explain structure and functions of the human eye. (20mks)
(a) What is mutation? (2mks)
Mutation is a sudden/spontaneous change; in the genetic make up of an organism
(b) Explain why certain bacteria and other pathogens become resistance to drugs after some time. (2mks)
bacterial that survive the drug will undergo mutation: to produce bacteria which are resistance to the prevailing condition/drug. (2mks)
(c) Work out a cross between a Haemophiliac man married to a carrier woman for Haemophilia.