Cells used in co-culture to maintain pluripotent stem cells. For human embryonic stem cell culture, typical feeder layers include mouse embryonic fibroblasts (MEFs) or human embryonic fibroblasts that have been treated to prevent them from dividing.
The joining of the male gamete (sperm) and the female gamete (egg).
In humans, the developing human from approximately eight weeks after conception until the time of its birth.
Fibroblast: A type of cell found in connective tissue throughout the body that produces collagen and other proteins found in the extracellular (between cells) spaces.