In humans, usually the cell growth up to the end of the seventh week in the mother's body
A rudimentary plant contained in the seed.
In the reproductive cycle, the stage after the fertilization of the egg that precedes the development into a fetus.
In viviparous animals, the young animal's earliest stages in the mother's body
The beginning; the first stage of anything.
An organism in the earlier stages of development before it emerges from the egg, or before metamorphosis.
A large membrane-bound vesicle in a cell's cytoplasm.
A small empty or air-filled space or vacuity.