Changes

When a stem cell divides, each new cell has the potential to either remain a stem cell or become another type of cell with a more specialized function, such as a [[muscle]] cell, a [[red blood cell]], or a [[brain]] cell.

When a stem cell divides, each new cell has the potential to either remain a stem cell or become another type of cell with a more specialized function, such as a [[muscle]] cell, a [[red blood cell]], or a [[brain]] cell.

Serving as a sort of repair system for the body, they can theoretically divide without limit to replenish other cells as long as the [[organism]] is still alive.  

Serving as a sort of repair system for the body, they can theoretically divide without limit to replenish other cells as long as the [[organism]] is still alive.  

*Broadly speaking, a stem cell is one that–in the course of cell division and increase in the numbers of cells–is able to reproduce itself and also mature into various specialized types of cells. The stem cell with the greatest potential (totipotential) is the fertilized [[egg cell]], which is capable of developing into a complete organism. [http://www.21stcenturysciencetech.com/articles/winter01/stem_cell.html]

*Broadly speaking, a stem cell is one that – in the course of [[cell division]] and increase in the numbers of cells – is able to reproduce itself and also mature into various specialized types of cells. The stem cell with the greatest potential (totipotential) is the fertilized [[egg cell]], which is capable of developing into a complete organism. [http://www.21stcenturysciencetech.com/articles/winter01/stem_cell.html]

==Controversy over human embryonic stem cell research==

==Controversy over human embryonic stem cell research==