Some definitions

Fertilization, which happens after pollination, is the fusion of the male reproductive cell (pollen) with the female reproductive cell (ovum) to form a zygote.

The male and female reproductive cells are usually haploid – they each have one copy of each chromosome. Once they combine, the resulting zygote is usually diploid - it has two copies of each chromosome.

The process of seed development is ultimately regulated by genetic controls, which can switch developmental processes on and off.

As a seed matures, seed filling is the process of transferring carbohydrates, lipids, proteins, and other components into the developing seed.

The stage of mass maturity is when maximum seed dry matter has accumulated, at the end of the seed filling phase.

During seed dispersal, seeds are spread or transported away from the parent plant, giving them the chance to germinate and grow into new plants.

The embryo of a seed is the tiny, furled up living baby plant, which in future may become a full adult plant.

Attached to the embryo are the cotyledons, stores of nutrient that protect and nourish the growing embryo, and become the new plant’s first leaves.

Seeds of some species, such as cereals, have most of their food storage reserves in tissue called the endosperm. Other species, such as legumes, have food storage in their cotyledons, while yet other species have a combination of both these food storage systems.