A newly developing human is typically referred to as an embryo until the ninth week after conception, when it is then referred to as a fetus. In other multicellular organisms, the word …

Dec 28, 2025 · An embryo is the early developmental stage of an animal while it is in the egg or within the uterus of the mother. In humans the term is applied to the unborn child until the end …

: an animal in the early stages of development that are marked by cleavage, the laying down of the basic tissues, and the formation of primitive organs and organ systems compare fetus. : a …

embryo An organism in its earliest stages of development, especially before it has reached a stage at which it can be distinguished from other species. The human embryo is so called up …

Oct 14, 2025 · An embryo is the early stage of development and lasts from week five to week 10 of pregnancy. A fetus is the later stage of development and lasts from the end of week 10 until …

Aug 13, 2023 · An embryo is a newly fertilized egg (zygote) up till the eighth week of development as it transforms through the morula, blastula, gastrula, and organogenesis stages.

Jul 21, 2025 · An embryo represents the initial stage of development in a multicellular organism. This period is characterized by rapid cell division and the establishment of the basic body plan.

Between the eighth week of development and birth a human embryo is called a foetus.

Aug 14, 2025 · The Embryo Project is supported by the National Science Foundation, Arizona State University, Center for Biology and Society, the Max Planck Institute for the History of …

In humans, the embryo is defined as the organism from the time of implantation in the uterus until about the eighth week, while the fetus is the stage from this time until birth.