Describe how seeds and fruits are suited to their modes of dispersal. (20marks)

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Q 
.Dispersed by wind
-Seeds / fruits are light in weight / small in size; to be carried easily away;
- Some have wing like structures; to increase surface area for them to remain buoyant / float in the air;

- Some have perforations; and hang on a slender stalk; when swayed the seeds are scattered away;
  Water dispersed
-Fruits / seeds have fibrous mesocarp; with a lot of air spaces for buoyancy;
            - Fruits / seeds have impermeable seed coat / mesocarp to avoid soaking;
Animal dispersed
-          Fruits / seeds have hooks; to stick on to animal body and carried away
-          Some fruits seeds are freshly; scented; brightly coloured; to attract animals which may carry them away.
-          Some seeds / fruits have hard / indigestible seed coats; and are released in animal droppings away from parent plants;
Self dispersal / explosive mechanism
            -Some when dry split open along lines of weakness and scatter the seeds away;
                                                                                                                                    (23pts max.20mks)

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