<span>Stem cells. There are two types of stem cells: adult stem cells - these are unspecialised cells that can develop into many (but not all) types of cells. Embryonic stem cells - these are unspecialised cells that can develop into any type of cell. And that's all! ;)
Hope this is useful !!!^_~!!!</span>
Scientists use fossils to learn about organisms' lives and evolutionary relationships, to understand geological change, and even to locate fossil fuel reserves.
Each cell in the human body contains about 25,000 to 35,000 genes.
The answer is amino acid.
