Because the egg cell is only 100 micrometers, or one-tenth of a millimeter, wide, we monitor this fine surgical extraction with a microscope (see previous image ... stem cells grown in culture ...

By cultivating cells in artificial media, researchers can study cell behavior, test new drugs, and produce biological materials, such as vaccines and therapeutic proteins. This image highlights the ...

Mammalian epithelial cells also turn over regularly, typically every few days. Whenever stem cells are called upon to generate a particular type of cell, they undergo an asymmetric cell division.