a) Give illustrated description of a named flower, state its method of pollination. (7 marks) (b) Review the typical differences that may be recognized between insect-pollinated and wind- pollinated flowers. (8 marks) (c) Discuss relative advantages and disadvantages of insect and wind pollination. (5 marks)

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a) Give illustrated description of a named flower, state its method of pollination. (7 marks)
Any suitable named flower is acceptable and must be discussed on the basis of the following:
- Non essential parts: petals and sepals description (colour, texture, fusion, number, etc);
- The male parts: the anthers and the filaments (numbers; height; colour, etc)
- The female parts: style, ovary and stigma (number, colour, texture etc»
- Any other special characteristics e.g. nectar guides should be included;
- Agent of pollination must be stated based on the features given;

Note: for a wind pollinated grass flower; C/ear distinction between an inflorescence; a spike/et and a flower is very important;
Use of diagrams for illustrations is encouraged;
(b) Review the typical differences that may be recognized between insect-pollinated and wind- pollinated flowers. (8 marks)

Differences must be corresponding; Any four correct differences 2 x 4 = 8 marks;

(c) Discuss relative advantages and disadvantages of insect and wind pollination. (5 marks)
- In wind pollination the chances of any pollen grain landing on a stigma is of the right plant are slim;
so large amounts of pollen are produced;
- Insect pollination is much more efficient than wind pollination because less pollen gets wasted and
so less is produced;
- Wind pollination works only well for plants that exist in large numbers in a particular area; insect
pollination can be applicable even in plants that occur singly;
- Because of the need to be conspicuous insect pollinated flowers invest a large amount of energy in
making large petals; at the expense of gamete formation hence fewer number of gametes; wind pollinated flowers produce large amounts of pollen;
- Wind pollination is more susceptible to weather; than insect pollination

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