The zygote, after fertilisation in plants, divides several times to form an embryo, which is the future plant. This embryo is enclosed inside the ovule. The ovule, gradually hardens and develops into a small, tough and persistent structure, which encloses the embryo, called the seed.

This seed, when under favourable conditions of soil, water and air, develops into a seedling, a process known as germination. This germinated seedling further is involved in the development of new plant. This way, the seed helps in reproduction.