Stem Cells

Question 1

How can stem cells repair

Answer 1

• stem cells can differentiate
• stem cells divide

Question 2

Why is using stem cells from same person better than using stem cells from different person

Answer 2

• cells will have same DNA
• same antigens / blood group
• less risk of rejection
• no immune response
• no risk of infection

Question 3

What is a stem cell

Answer 3

• unspecialized cells…
• which can differentiate to be any cell type
• and then divide by mitosis (self-replicating)

Question 4

Two types of stem cells

Answer 4

• embryonic stem cells
• adult stem cells

Question 5

Where adult stem cells found

Answer 5

• bone marrow (mostly)

Question 6

Where are embryonic stem cells found

Answer 6

• early embryos

Question 7

Embryonic stem cells vs adult stem cells

Answer 7

• embryonic can become any type of cell
• adult stem cells can only become certain types of cells
• (like blood cells)

Question 8

Pros of using embryonic stem cells in medicine

Answer 8

• can differentiate into various cell types
• used

Question 9

What is a stem cell

Answer 9

• undifferentiated cell
• that can divide and produce specialized stem cells

Question 10

Define cell differentiation

Answer 10

• process by which cells become different, specialized cell types

Question 11

Uses of stem cells

Answer 11

• making nerve cells
• to repair broken spinal cords
• making heart cells
• to replace heart tissue that has been damaged by CHD
• making new retinal cells
• to cure blindness
• making pancreas cells
• that can make insulin
• to cure diabetes

Question 12

Pros of embryonic stem cells

Answer 12

• can make any cell types
• many spare embryos from IVF that would otherwise perish
• if cloned they have identical genes to patient
• so not rejected

Question 13

Cons of embryonic stem cells

Answer 13

• ethics: ‘killing’ potential human lives
• if spare embryos used from IVF, ES cells won’t be genetically identical to patient
• could lead to rejection
• human embryos are difficult to grow in culture + very fragile
• so inefficient cloning
• may be few potential donors
• since you need human eggs and embryos
• difficult to mak ES cells differentiate into the correct cell type(s)
• if incorrect differentiation, can lead to tumors and cancer

Question 14

Pros of adult stem cells

Answer 14

• no ethical issue
• easier to control, since already partially differentiated
• less likely to cause tumors
• no concerns over supply
• if patient’s own AS cells used, no rejection (since genetically identical)

Question 15

Cons of adult cells

Answer 15

• not all cell types can be produced
• difficult to extract
• AS cells age, so cells from elderly may not last long