Final answer:
Stem cells are fundamental cells that can divide and specialize into various tissue types. They can be derived from embryonic, adult tissues, cord blood, baby teeth, or created via induced pluripotency.
Step-by-step explanation:
When they talk about stem cells, they refer to the unspecialized cells capable of reproducing themselves through cell division, sometimes after long periods of inactivity.
Under certain conditions, stem cells can differentiate into more specialized, tissue-specific or organ-specific cells, possessing distinct functions.
Stem cells can be sourced from various locations: embryonic stem cells which offer high differentiation potential but raise ethical concerns.
Adult stem cells which are limited in their differentiation but are less likely to be rejected by the body, cells from umbilical cord blood and deciduous baby teeth which can be banked for future use, and induced pluripotent stem cells which avoid the pitfalls of both embryonic and adult stem cells.