The arouse for seed and fruit formation was the act of fertilization. This resulted to fertilization of double cangiosperms which produces two structures. That is, a diploid zygote or oospore and a triploid primary endosperm cell.
Nutritive tissue which is also called endosperm is realized as a result of the process. The embryo is forms by zygote. Endosperm offers nourishment to this growing embryo.during the growing of the embryo the central part of the endosperm is eaten up. Endosperm will later corrodes over the nucellus. Many seeds usually give the endosperm opportunity to persists in the seed as food storage tissue. Therefore, those seeds are usually called endospermic or aluminous, e.g., Castor, Maize, Wheat, Barley, rubber, coconut. But reverse is the case in some endosperm because they completely eaten up by growing embryo. But the food is store in cotyledons which the embryo later use to develop. Those kinds of seeds are called non-endospermic or exalbuminous, examples are Pea, Gram, Bean, Groundnut. Where as In some seeds nucellus remains persist. These residual nucellus which persists in the seed is called perisperm, examples are Black pepper, Coffee, Castor, Cardamom, Nymphaea. And as the embryo moving towards maturity but its growth is further suspended due to development of growth inhibitors, abscission of funiculus or changes in integuments. The cells of the integuments usually lose their protoplasm, develop thick and impermeable walls. The integuments though get transformed into seed coats, outer testa and inner tegmen. The moisture content of seed decreases and reaches up to 1
Wall of tissue of the ovary is arose to grow with the development of the seed. Which produces a fruit wall or pericarp. Thalamus and other floral parts also show proliferation along-with the development of the ovary wall in some situations. These fruits are refer to as false fruits, examples are Apple, Strawberry, Cashew. But in any fruit in which the part of the flower are not develop along-with ovary, those fruits are called true fruits. Other fruits can develop without fertilization. Those fruits are seedless fruits and are named parthenocarpic fruits like Banana. Parthenocarpy or production of seedless fruits can artificially induced by means of hormones.
