stem cells

STEM CELLS

Stem cells are single cells that can replicate, and differentiate and become a specialised cell. There are three types: embryonic, adult, and therapeutically-cloned stem cells. In plants, stem cells are found in the meristem tissue in the root (below the ground) tips and the shoot (above the ground) tips.

embryonic stem cells: made from embryos and can develop into any cell types (produced by embryos)

adult stem cells: only found in specific areas of the body and can only develop into a limited number of cell types (sourced in the bone marrow)

therapeutic stem cells: made through a process known as therapeutic cloning (specifically created for medical purposes)

pluripotent: ability to differentiate into all types specialised cells

STEM CELL TRANSPLANTS

In a stem cell transplant, embryonic stem cells are first specialised into the necessary adult cell type. Then, those mature cells replace tissue that is damaged by disease or injury. This type of treatment could be used to:

• replace neurons damaged by spinal cord injury, Parkinsons disease, or other neurological disease

• produce insulin that could treat people with diabetes and heart muscle cells that could repair damage after a heart attack

• replace virtually any tissue or organ that is injured or diseased

SOCIAL, ETHICAL, and CLINICAL ISSUES

• difficult to obtain donors and their stem cells

• cultured stem cells could be contaminated

• success is not guaranteed

• not viewed as a person

• at what stage should they be considered as a person

• is it right to create embryos and then destroy them

• exploiting patients - expensive treatment, developing process

• the public is not educated enough

• viruses could be transferred