Here's why:
* Unending cycles of cell division: Stem cells have the unique ability to divide indefinitely, producing both more stem cells and specialized cells that make up the tissues.
* Tissue maintenance: This constant renewal process ensures that tissues are constantly replenished with new cells, replacing damaged or worn-out ones.
There are two main types of stem cells:
* Embryonic stem cells: These stem cells are derived from the inner cell mass of a blastocyst (early embryo). They are pluripotent, meaning they can differentiate into any cell type in the body.
* Adult stem cells: These stem cells reside in specific tissues and are multipotent, meaning they can differentiate into a limited number of cell types within that tissue. For example, hematopoietic stem cells in bone marrow produce various blood cells.
Other terms you may encounter:
* Progenitor cells: These are cells that are more specialized than stem cells but still retain the ability to divide and differentiate into a limited number of cell types.
* Somatic cells: These are any cells in the body other than gametes (sex cells). Most somatic cells are not stem cells and have a limited lifespan.
