Stem cells

Most of the cells in your body are differentiated, but there are some that are completely unspecialised stem cells. They can differentiate into many different types of cells when they are needed. Human stem cells are found in embryos and in some adult tissue like bone marrow.

Function of stem cells:

When a sperm and egg cell meet, they form an embryo, forming a single cell. This cell divides and the embryo is soon a hollow ball of cells, the inner cells of this ball are the stem cells which will eventually differentiate. 

Scientists now think there is a tiny amount of stem cells in most of the different tissues in your body. This includes your blood, brain, muscle and liver.

The stem cells stay there until they are needed to repair or replace damaged cells.

Using stem cells:

Many people die because parts of their bodies aren't working correctly. For example, spinal injuries cause paralysis because the spinal nerve cells do…