Introduction to stem cells
This is a core JC1 topic in H2 BIO A levels. This topic explores how some of the cells of a multi-celllar organism take on the special role of tissue renewal in addition to self-renewal. It also describes the 3 specific stem cell types, their definitions as well as ethical issues of their usage in science and medicine.
- Stem cells divide extensively.
- Stem cells proliferate and differentiate by mitosis.
- When somatic cells are injured, stem cells repair damaged cells.
- Stem cells are unspecialised cells that differentiate to specialized cells, in the process they lose genes that have no function in these cells.
- Differentiation ≠ cell division.
- Self-renewal ≠ tissue renewal.
- Ethical implications are fairly open-ended so long as you present coherent points, with elaboration!
- Do not answer questions on ethical implications with a series of unanswered questions. E.g. what if patient didn’t know…?