Egg cell
Videos
The egg cell or ovum is the female reproductive cell, or gamete, in most anisogamous organisms. The term is used when the female gamete is not capable of movement. If the male gamete is capable of mov
Ovum and sperm fusing together
Gene expression pattern determined by histochemical GUS assays in Physcomitrella patens. The Polycomb gene FIE is expressed (blue) in unfertilized egg cells of the moss Physcomitrella patens (right) and expression ceases after fertilization in the developing diploid sporophyte (left). In situ GUS staining of two female sex organs (archegonia) of a transgenic plant expressing a translational fusion of FIE-uidA under control of the native FIE promoter
Embryo
Videos
An embryo is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilizati
A human embryo seven weeks after conception (nine weeks gestational age)
Embryos (and one tadpole) of the wrinkled frog (Rana rugosa)
Mouse and snake embryos
The inside of a Ginkgo seed, showing the embryo