Tag: growth and development in plants

A fruit is the seed-bearing structure in flowering plants (also known as angiosperms) formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate seeds. The outer, often edible layer, is the pericarp, formed from the ovary and surrounding the seeds, although in some species other tissues contribute to or form the edible portion. The pericarp may be described in three layers from outer to inner, the epicarp, mesocarp and endocarp. A fruit results from maturation of one or more flowers, and the gynoecium of the flower(s) forms all or part of the fruit

Fertilization occurs when one of the sperm cells fuses with the egg inside of an ovule. After fertilization occurs, each ovule develops into a seed. Each seed contains a tiny, undeveloped plant called an embryo. The ovary surrounding the ovules develops into a fruit that contains one or more seeds.

After fertilization process, the different cells in the embryo sac develops to form several parts of the embryo. For instance, the outer integument forms testa, inner integument forms tegmen and ovary wall forms pericarp.

The haploid sperm and haploid egg combine to form a diploid zygote, while the other sperm and the two haploid polar nuclei of the large central cell of the megagametophyte form a triploid nucleus. It will later develop into the endosperm, nutrient tissue which provides nourishment to the developing embryo.

The fruit of the coconut is a large, dry drupe composed of a thin outer layer (exocarp), a thick, fibrous middle layer called as a mesocarp and a hard inner layer called as an endocarp that surrounds a large seed. A small, cylindrical embryo is embedded in the endosperm nutritive tissue just opposite the functional germination pore. The seed is surrounded by an outer brown layer called as the seed coat or testa.
Thus, the correct answer is option D.