Embryo

Definition

An embryo is an early stage of development for multicellular organisms, following fertilization and lasting until the beginning of the fetal stage. In humans, this period covers the first eight weeks after fertilization, during which all major organs and structures begin to form.

Related terms

Fertilization:

The process by which male and female reproductive cells (gametes) join to form a new cell (zygote).

Zygote:

The initial cell formed when a new organism is produced by sexual reproduction, containing genetic material from both parents.

Organogenesis:

The phase in embryonic development where organs are formed and differentiated from simple structures