a fertilized egg in the early stage of development prior to cell division
A zygote, morula, blasotcyst or embryo before it develops a "primitive streak."
describes a developing organism in the period between fertilization and implantation. See preimplantation embryo.
The term used by ethicists to denote the stage from fertilization to about two weeks after implantation when the fetal plate forms and when the implanted pregnancy can no longer split into more than one individual. (Embryologists commonly refer to all stages beyond fertilization as the "embryo.")
The fertilized egg that is produced outside the uterus during IVF.
a fertilized egg which is in the process of early cell division up to the 16 cell stage (up to about day 14 for humans). During these early divisions no differentiation of cells has occurred. Each of these cells has the potential to become a separate individual if the cell becomes separated from the zygotic cell mass. (Identical twins, identical triplets, etc. are formed in this way.)
A fertilized ovum (or conceptus) prior to implantation and the beginning of pregnancy.
A fertilized egg before cell division begins.
