Waec Biology Past Questions For Year 2006
Question 46
Which of the following orders correctly represents the trend in eutrophication?
- A. Lack of oxygen → Death of aquatic organisms → Massive algal growth
- B. Excess nitrates and phosphates → Massive algal growth → Lack of oxygen → Death of aquatic organisms
- C. Heavy mineralization → Lack of oxygen → Massive algal growth
- D. Excess nitrates and phosphates → Lack of oxygen → Massive algal growth → Death of aquatic organisms
Question 47
An effective management of natural resources to ensure their continued yield from generation to generation may involve all the following except
- A. protection of wildlife
- B. prevention of habitat destruction
- C. biological control of pests
- D. disposal of raw sewage into the sea
Question 48
Air pollution can be reduced by the following methods except?
- A. building tall factory chimneys
- B. passing waste gases through filters and absorbers
- C. using lead-free petrol in car
- D. recycling tins, cans and bottles
Question 49
Which of these diseases cannot be spread by an insect?
- A. Cholera
- B. Malaria
- C. Trypanosomiasis
- D. Measles
Question 50
The contrasting pair of genes affecting a trait and located at the same position on homologous chromosomes is
referred to as
- A. chromatids
- B. mutants
- C. alleles
- D. chromatin
