All three are stem cells, but they differ in potency: the range of specialized cell types into which they can differentiate. Totipotent cells have the widest potential, pluripotent cells can form any body cell type, and multipotent cells can form only a limited range of related cell types.
This is part of IB Biology B2.3 Cell specialization and is assessed at both SL and HL.
| Stem cell type | Developmental potential | IB-relevant example |
|---|---|---|
| Totipotent | Can differentiate into every body cell type and extraembryonic tissues, so the cells collectively have the potential to form a complete organism. | Cells in a very early-stage animal embryo. |
| Pluripotent | Can differentiate into nearly every body cell type, but not all extraembryonic tissues; therefore, they cannot independently form a complete organism. | Embryonic stem cells after the earliest developmental stages. |
| Multipotent | Can differentiate into a restricted group of related cell types within a particular tissue or developmental pathway. | Adult stem cells in bone marrow can produce different types of blood cell. |
As development proceeds, cells usually become more specialized and their potency decreases:
totipotent → pluripotent → multipotent → differentiated cell
This occurs through cell differentiation, in which different patterns of gene expression cause cells with the same genome to develop different structures and functions. Stem cells also retain the capacity to divide repeatedly, allowing them to maintain a stem-cell population while producing cells that differentiate.
A common misconception is that “pluripotent” means able to form a whole organism. It does not: only totipotent cells have the capacity to produce both body tissues and all tissues needed for complete development.
Exam technique: For a command term such as distinguish, state the developmental potential of both cell types being compared. Do not merely say that one is “more powerful”; specify the range of cells each can produce and include an appropriate example.
