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

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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 fro 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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