- Multicellular organisms are made up of many different cell types that are specialised for their function.
- All of these cell types originally came from stem cells.
- Stem cells are unspecialised cells - they can develop into any type of cell. All multicellular organisms have some form of stem cells e.g. humans in early embyros and bone marrow.
- Stem cells divide to become new cells, which then become specialised. This is called differentiation.
- In animals, adult stem cells are used to replace damaged cells.
- In plants, stem cells are found in the cambium. Stem cells in the vascular cambium differentiate to become xylem and phloem.
Specialised Cells- Animals
Erythorocytes (red blood cells)
- Biconcave disc…