(a) mention four caste found among termite nests (b)(i) state one role of each caste to the colony. (ii) mention two ways by which termites are of economic ...

Answer Details

(a) Four castes in a termite nest

Queen, king, workers, and soldiers.

(b)(i) Role of each caste

• Queen: the only fully fertile female; she lays all the eggs and so reproduces to build up the colony.
• King: the fertile male that mates with the queen to fertilise her eggs.
• Workers: sterile insects that build and repair the nest, gather food, feed the queen, king and young, and keep the nest clean.
• Soldiers: sterile insects with large heads and strong jaws that defend the colony against enemies.

(b)(ii) Two economic importances of termites to man

• Harmful: they destroy wooden buildings, furniture, books, crops and paper, causing great loss.
• Useful: they help to break down (decompose) dead wood and plant matter, enriching and aerating the soil; their mounds provide fertile soil; and they serve as food (source of protein) for people and animals.

(c)(i) Two types of courtship behaviour in lower animals

Sound/vocal display (for example croaking in male toads, chirping in crickets), colour/visual display (for example nodding and colour change in the Agama lizard), release of scent (pheromones), and nuptial dance/movement display. (Any two.)

(c)(ii) Two importances of courtship behaviour in reproduction

• It attracts a mate of the same species and of the opposite sex, ensuring successful mating.
• It prepares the partners and synchronises the release of gametes, so that fertilization succeeds and interbreeding between different species is avoided.

(d) Courtship behaviour of the Agama lizard

The male Agama lizard (rainbow lizard) attracts a female by a display of colour and movement. During courtship the male develops bright colours, with an orange or reddish head and a bluish body. He carries out repeated up-and-down movements of the head and the front part of the body (head-bobbing or press-up movements), often on a raised surface, to attract the attention of the female. This display also warns off rival males and marks his territory. When a female is attracted and becomes receptive, the two mate.