Stem Cells

Question 1

What are stem cells?

Answer 1

Undifferentiated cells that can divide by mitosis to become new cells, which then differentiate

Question 2

Give two types of stem cells.

Answer 2

• Embryonic stem cells
• Adult stem cells

Question 3

What are embryonic stem cells?

Answer 3

• Found in early human embryos
• They are able to divide and produce any type of cell
• Important for growth and development of organisms

Question 4

What are adult stem cells?

Answer 4

• Only found in certain places, like bone marrow
• They are less versatile as they can only produce certain cell types
• Used to replace damaged cells in animals

Question 5

Name the plant tissue that produces stem cells.

Answer 5

Meristem tissue

Question 6

Where is meristem tissue found in plants?

Answer 6

In areas that are growing, such as the tips of the roots and shoots

Question 7

(Exam-style question)

Describe the function of meristems in the growth of a plant.

Answer 7

• Meristems are the only place in a plant that produce stem cells that are able to divide by mitosis
• The new cells produced are able to differentiate into any type of cell in the plant, contributing to its growth

Question 8

What can stem cells in plants be used to do?

Answer 8

• Grow more rare species, preventing extinctions
• Create identical plants with desired features e.g. disease resistance

Question 9

(Exam-style question)

Explain one reason why scientists may prefer to use embryonic stem cells for research rather than adult stem cells.

Answer 9

Embryonic stem cells have the potential to produce any type of cell, whereas adult stem cells are less versatile

Question 10

Suggest one reason why people are against research involving embryonic stem cells.

Answer 10

Some people think it’s wrong to destroy a potential human life

Question 11

Give 3 potential risks scientists need to consider before transplanting stem cells to cure diseases.

Answer 11

• Tumour development
• Disease transmission
• Rejection

Question 12

Describe the risk of a tumour developing when transplanting stem cells.

Answer 12

A tumour may develop inside the patient if the rate at which the transplanted cells divide can’t be controlled

Question 13

Describe the risk of disease transmission when transplanting stem cells.

Answer 13

There may be a risk of disease transmission from the donor to the recipient if viruses are present within the transplanted cells

Question 14

Describe the risk of rejection when transplanting stem cells.

Answer 14

There may be a risk of an immune response being triggered if the transplanted cells have not been grown using the patient’s own stem cells