the cell resulting from the union of an ovum and a spermatozoon (including the organism that develops from that cell)
A fluid-filled sphere formed about 5 days after fertilization of an ovum that is made up of an outer ring of cells and inner cell mass. THis is the structure that implants in the endometrium of the uterus.
process by which unspecialized cells develop into their mature forms and functions
most animals have three layers of cells early in embryonic development each layer gives risse to different body structures
the inner germ layer that develops into the lining of the digestive and respiratory systems
the middle germ layer that develops into muscle and bone and cartilage and blood and connective tissue
embryonic stem cells
an undifferentiated cell, taken from an embryo that has potential to give rise to various other cell or tissue types
adult stem cells
Cells present in adult tissues that generate replacements for nondividing differentiated cells that can be of great therapeutic potential.