Theory:

Fruit and Seed Formation
After fertilisation, the ovary develops into the fruit, and ovule develops into the seeds. The outer parts of flower - petals, sepals and stamen dries out and falls off. The zygote inside the ovary obtains nutrition from the ovule and grows to form an embryo. Parts of the ovule develops into the seed covering or the protective seed coat. Fruits are the ripened ovary of a flower.
 
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Some fruits are fleshy and juicy, e.g. mango, apple and orange.
 
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In contrast, some are hard, like almonds and walnuts.
 
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Seed Dispersal
Seeds are produced from the ovule. Plants produce a lot of seeds. When the seeds fall down, they start germinating. If a large number of seeds falls in the same place, there will not be enough space, water, minerals and light, and there will be competition among plants. Thus, the seeds are moved away by external agents to far off places.
The process through which seeds are scattered to different places is called seed dispersal.
Seeds and fruits are dispersed through various agents like wind, water, birds and few animals. 
  • It may also take place by explosion or bursting of fruits naturally.