Embryo, from which a new plant grows, is is contained in a seed. The seed also contains a food stored to nourish the embryo until it develops roots and leaves.
The seed is enclosed in a tough coat to protect it from drying out. Many seeds are dispersed by the wind.
Other seeds have wings that allow them to glide and get dispersed. Some seeds are dispersed by plants and animals. Water also helps in the dispersal of seeds. All seeds help a new plant of its kind to grow.
Below Seeds info from Wikipedia (Read More):-
A seed (en-us-seed.ogg /ˈsiːd/ (help·info)), referred to as a kernel in some plants, is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant. The formation of the seed completes the process of reproduction in seed plants (started with the development of flowers and pollination), with the embryo developed from the zygote and the seed coat from the integuments of the ovule.
Seeds have been an important development in the reproduction and spread of flowering plants, relative to more primitive plants like mosses, ferns and liverworts, which do not have seeds and use other means to propagate themselves. This can be seen by the success of seed plants (both gymnosperms and angiosperms) in dominating biological niches on land, from forests to grasslands both in hot and cold climates.
http://en.wikipedia.org/wiki/Seeds
