Theory question 106
Excretion(a) Copy and complete the table below.
Disease | one effect | one remedy
Kidney stone | |
Nephritis | |
Diuresis | |
(b) Make a labelled diagram of the carbon cycle. (c)(i) What is an Estuarine habitat? (ii) Construct a food chain typical of an Estuarine habitat. (d)(i) Name two pests and two diseases that can attack plant crops. (ii) State three ways of controlling plant diseases. (e) State four functions of a public health authority. (f) State four ways of maintaining food hygiene in the community.
Show the model answer
(a) Kidney stone – effect: severe pain in the back/abdomen, blocked urine flow or blood in urine; remedy: drink plenty of water, drugs to dissolve the stone, or surgery/laser removal.
Nephritis – effect: kidneys fail to filter properly, protein/blood in urine, swelling (oedema), high blood pressure; remedy: antibiotics, low-salt and low-protein diet, dialysis or kidney transplant.
Diuresis – effect: passing large amounts of urine, leading to dehydration and loss of salts; remedy: drink fluids and replace salts, treat the cause (e.g. control diabetes), antidiuretic drugs.
(b) Diagram with arrows: CO2 in the air → photosynthesis by green plants → carbon compounds in plants → feeding → animals; respiration of plants and animals → CO2; death → decomposers (decay, respiration) → CO2; fossil fuels → burning (combustion) → CO2. Title and labels needed.
(c)(i) An estuary is where a river meets the sea; the water is brackish (salinity changes with the tide) and the bottom is muddy.
(ii) e.g. Phytoplankton → shrimps → tilapia/mudskipper → kingfisher (any correct chain of three or more estuarine organisms).
(d)(i) Pests, any two: locusts, aphids, weevils, stem borers, rodents, birds, nematodes. Diseases, any two: maize rust, cassava mosaic, rice blast, cocoa black pod, groundnut rosette, maize smut.
(ii) Any three: use resistant varieties; spray fungicides or other chemicals; crop rotation; remove and burn infected plants; plant clean, disease-free seeds; control insect vectors; good spacing and weeding.
(e) Any four: provide safe water; proper disposal of refuse and sewage; inspect food, markets and abattoirs; vaccination and immunisation; control of disease vectors; health education; quarantine and isolation of infectious cases; inspect houses and premises.
(f) Any four: wash hands before handling food; cover food from flies and dust; cook food well; wash fruits and vegetables; store food in clean containers or refrigerate; keep kitchens and utensils clean; food handlers should be medically checked; dispose of waste properly.
Section C (candidates in Nigeria only). Keep each table answer short: one effect and one remedy per disease.