Cell Biology pt2

Stem cells

Embryonic stem cells can turn into any type of cell. Undifferentiated cells can divide to produce lots more undifferentiated cells. Stem cells are found in early human embryos. Stem cells from embryos and bone marrow can be grown ina  lab to produce clones and made to differentiate into specialised cells to use in medicine or research.
Medicine already uses adult stem cells to use disease.
Embroyonic stem cells could also be used to replace faulty cells in sick people - you could make insulin-producing cells for people with diabetes etc. In theraputic cloning, an embryo could be made with the same genetic info as the patient. This means that the stem cells produced would contain the same genes so less chance of it being rejected. However there are risks involved in using stem cells in medicine. E.g. stem cells from the lab may become contaminated with a virus which could be passed on to the patient.
Some people are against stem cell research:
1) Some believe that human embryos shouldn't be used for experiments since each one is a potential human life - others think it is worth it to save a human life
2) The embryos used in the research are usually unwanted ones from fertilty clinics which would probably be destroyed if not used.
3) Campaigners think that scientists should concentrate on finding and developing other sources of stem cells.
4) In some countries stem cell research is banned. It's allowed in the UK but has to follow strict guidelines.
Stem cells can also be used to produce identical plants. Throughout the plant's life, cells in the meristem tissue can differentiate into any type of cell plant. These stem cells can be used to produce clones of whole plants quickly and cheaply. They can be used to grow more plants of rare species.

Diffusion

This is the…