Topic 1a - cell structure and cell division ( 8. Stem cells )

Question 1

What are stem cells?

Answer 1

Stem cells are undifferentiated biological cells that can differentiate into specialised cells and can divide (through mitosis) to produce more stem cells (basically, they are cells which we can manipulate to become whatever we want e.g. organs).

Question 2

Why are stem cells useful?

Answer 2

• Stem cells can be made to differentiate into many different types of cells e.g. nerve cells
• There is currently a lot of research involving the use of stem cells to treat various diseases and injuries
• Cells can be taken from human embryos, adult bone marrow and umbilical cords
• Treatment with these cells may help cure conditions such as paralysis

Question 3

Are there any ethical considerations regarding stem cells?

Answer 3

There are very few stem cells in an adult so most come from human embryos and many people feel that all embryos have the potential to become a baby and that they should not be used in this way. Some feel it is unethical because the embryo cannot give permission so its human rights are being violated. They could cause cancer if used in sick people (has been seen with mice).

Question 4

What is therapeutic cloning?

Answer 4

using cells from an adult to produce a cloned early embryo of themselves (useful for growing organs the donor will not reject)

Question 5

How are scientists hoping to overcome ethical objections to using embryonic stem cells?

Answer 5

using embryonic stem cells in umbilical cord blood of newborns, using adult stem cells in bone marrow and other tissues (can only develop into limited range of cell types)

Question 6

To date, what have adult stem cells successfully treated?

Answer 6

some forms of heart disease, new organs such as tracheas grown