(a) Complete the table below;
| Disease | Causative organism | Vector | Control |
| Cholera | |||
| Trypanosome | |||
| Female Anopheles mosquito | |||
| Ringworm | None |
(b) Explain briefly the biological basis of preserving foods using each of the following methods;
(i) salting (ii) irradiation (iii) smoking
Explanation
(a)
| Disease | Causative Organism | Vector | Control |
| Cholera | Vibrio Cholerae | Housefly/Cockroach | Good sanitation/good personal hygiene/ any other method of good sanitation/inoculation/vaccination |
| Trypanosomiaasis/Sleeping sickness | Trypanasome | Tsetsefly/Glossina | Destroying habitat of vector/clearing the vegetation, killing vector/ eradicate flies. |
| Malaria | Plasmodium sp | Penale anopheles mosquito | Proper sanitation/using spraying recommended insecticide/fumigation, clearing of bushes/drainages of breeding sites/sleeping under nets. |
| Ringworm | Tinea Sp/Fungi/Microsponium | None | Good personal hygiene, avoid contact with infected persons/material, use of drugs/griseofluvin |
(b) Biological Basis of Preserving Foods by;
(i) Salting; Removes water/moisture from food by osmosis therefore prevents micro-organisms from growing on food by dehydrating and killing them.
(ii) Irradation; Involves the exposure of food to high energy gamma rays/x-rays radiation to destroy enzymes that cause spoilage, delay ripening of fruits, sprouting of vegetables therefore allowing long storage periods.
(iii) Smoking; Reduces the water content of food thereby creating unfavourable conditions for microbial growth and survival also called curing. Smoking contains phenols/carbon that kills microbes on the surface of food.