WAEC Biology 2016 Theory — Question 5

Model answer

(a) Differences between tactic and nastic movement: Tactic movement is a directional response while nastic movement is non-directional. Tactic movement involves the whole organism while nastic movement involves only a part of the organism. (b)(i) Examples of organisms that show tactic movement: Chlamydomonas and Euglena. (ii) Examples of organisms that show nastic movement: The four-o'clock plant and the sensitive plant (Mimosa). (c)(i) Ways of caring for the mammalian skin: By protecting the skin from injury Regular washing with soap and water By avoiding excessive exposure to radiation (ii) Stimuli to which the mammalian skin is sensitive: pain, touch, pressure, cold and heat. (d) Effects of high temperature on a terrestrial habitat: It can cause bush fire It makes animals uncomfortable It causes plants to wither It increases the rate of decay It increases the rate of water loss by the organisms (e)(i) Courtship behaviour refers to a type of behaviour in animals which is aimed at attracting a mate for the purpose of copulation/reproduction. (ii) Courtship behaviours in animals: (examples include displaying colourful plumage, singing/calling, and dancing/specific movements) (f) Organisms that carry out holozoic mode of nutrition: dogs, cats and rats. (g) The materials found at the scene of an accident/crime should be checked for fingerprints. Since no two humans can have exactly the same fingerprint, the suspect whose fingerprint matches that on the materials is responsible for the crime in question.