world war 2 history
world war 1 and 2 history  
search
 
 
 

Embryo

Embryos (and one ) of the wrinkled frog (Rana rugosa).
Enlarge
Embryos (and one tadpole) of the wrinkled frog (Rana rugosa).
For musical bands with the name "Embryo" see Embryo (band)

An embryo (Greek: έμβρυον) is an animal or a plant in its earliest stage of development.

  • Plants: In botany, a plant embryo is part of a seed, consisting of precursor tissues for the leaves, stem (see hypocotyl), and root (see radicle), as well as one or more cotyledons. Once the embryo begins to germinate — grow out from the seed — it is called a seedling.
  • Animals: The embryo of vertebrates is defined as the stages between the first division of the zygote (a fertilized ovum) until it becomes a foetus. An embryo is called a foetus at a more advanced stage of development and up until birth or hatching. In humans, this is from the eighth week of gestation.

See also

A chick embryo of thirty-three hours' incubation
Enlarge
A chick embryo of thirty-three hours' incubation

External link

The contents of this article are licensed from Wikipedia.org under the
GNU Free Documentation License. How to see transparent copy
08-19-2006 14:03:27
 
World War Diary.com | Legal info