WASSCE JUNE 2012 BIOLOGY 2 THEORY QUESTIONS ESSAY AND ANSWERS
1 (a) Explain briefly four factors that affect the diffusion of substances
(b) Explain the following terms (i) active transport (ii) transpiration.
(c) State four ways by which plants can reduce high rate of transpiration.
(d) State the features of red blood cells and how these features adapt the cell to perform its functions.
2 (a) Describe briefly the role of the stomach in digestion.
(b)(i) Name three parts of the plants in which food can be stored. (ii) Give one example in each case.
(c) Explain briefly how the level of sugar in the mammalian blood can be regulated .
3 (a) Explain briefly the following terms:
(i) conservation; (ii) endagered species
(b) State : (i) five reasons why conservation of forests is important; (ii) four ways by which forest reserves can be conserved
(c) (i) What is the importance of decomposers in the ecosystem ?
(ii) Name one plant and one animal decomposer.
4 (a) (I) What is a gene ?
(ii) Diffentiate between the terms genotype and phenotype.
(b) Explain the following terms : (i) hybrid (ii) pure breeding; (iii) nucleotide
(c) In garden pea seeds, smooth seed coat is dominant over rough seed coat. With the aid of a genetic diagram, determine the result expected if a homozygous rough pea is crossed with a smooth seed coat plant whose parents were rough coated.
FOR CANDIDATES IN NIGERIA ONLY
7 (a) Explain the following terms:
(i) disease; (ii) symptoms of diseases
(b) (I) List two physical and two chemical barriers that prevent pathogens from penetrating the body of an organism.
(ii) Explain how vaccination protects the body from contracting infectious diseases.
(c) Distinguish between an antiboby and an antigen.
(d) Name the causative agents of :
(I) Malaria; (ii) Cholera; (iii) AIDS.
8 (a) (I) Describe epigeal germination of seed.
(ii) In a tabular form, state three differences between epigeal germination and hypogeal germination.
(b) (I) What is seed dormancy? (ii) State three ways by which dormancy in seeds can be broken.
(c) State six advantages of using contraceptives in human populations.