Stem cells

Question 1

What are stem cells?

Answer 1

Undifferentiated cells that arent adapted to a specific function + have the potential to differentiate to become any specialised cell type

Question 2

Stem cells divide repeatedly as the source for new cells, what are these cells needed for?

Answer 2

Growth, tissue repair, and development

Question 3

What happens once a stem cell has differentiated?

Answer 3

It enters the G0 phase of the cell cycle, and is no longer able to divide

Question 4

What is the result of too much division?

Answer 4

Stem cells cause masses of cells called tumours, which can develop into cancer

Question 5

What is the result of too little division?

Answer 5

Tissues arent efficiently repaired

Question 6

What is potency?

Answer 6

A stem cell’s ability to differentiate into different cell types

The more cell types it can produce, the greater its potency

Question 7

Explain totipotent stem cells:

Answer 7

• Can produce a whole organism
• Fertilised egg or zygote
• Apical meristems

Question 8

Explain pluripotent stem cells:

Answer 8

• Form all tissue types but not whole organism
• Early embryos
• Plant lateral meristems

Question 9

Explain multipotent stem cells:

Answer 9

• Forms range of cells within a certain type of tissue

E.g. Haemotopoietic cells in bone marrow