B2 Stem Cells And Diffusion

Question 1

What is a Stem Cell?

Answer 1

A cell that has not yet been specialised.

Question 2

Embryonic stem cells can do what?

Answer 2

Can turn into any type of cell.

Question 3

What may stem cells be able to do?

Answer 3

Cure diseases. Embryonic stem cells may be able to replace faulty cells.

Question 4

Advantage of Adult stem cells?

Answer 4

Plentiful supply. No ethical issues as permission can be given. Well tested.

Question 5

Disadvantage of adult stem cells?

Answer 5

Painful to extract. Fewer diseases can be treated. Can only form the type of cells as the tissue they were taken from.

Question 6

Advantage of Embryonic stem cells?

Answer 6

Has potential to develop into any type of cell/tissue. Used to treat human disease. Painless.

Question 6

Disadvantage of Embryonic stem cells?

Answer 6

Unethical- embryos cannot give permission. Possible harm/death to embryo.

Question 8

What is diffusion

Answer 8

Diffusion is the SPREADING OUT of particles from an area of HIGHER CONCENTRATION to an area of LOWER CONCENTRATION.

Question 9

Why can diffusion only happen in gases/liquids?

Answer 9

Because the particles in these substances are free to move randomly.

Question 10

What affects the rate of diffusion?

Answer 10

Concentration gradient. Temperature. Surface area.

Question 11

How does concentration affect diffusion?

Answer 11

Greater the difference in concentration, the faster the rate of diffusion.