1.4 Cell Differentiation

Question 1

what is cellular differentiation?

Answer 1

• the process by which a cell expresses certain genes to produce proteins characteristic for that type of cell.
• this allows a cell to carry out specialised functions.

Question 2

where are meristems found and what is their function?

Answer 2

• found in plants

- regions of unspecialised cells in plants that can divide (self-renew) and/or differentiate

Question 3

what are the two types of stem cells in animals and where they are found

Answer 3

embryonic stem cells-found in the very early embryo

tissue stem cells-found throughout the body in adults and children

Question 4

what is the function of embryonic stem cells?

Answer 4

• they can differentiate into all the cell types that make up the organism
• so they are pluripotent.
• all the genes can be switched on so these cells can differentiate in to any type of cell

Question 5

what is the function of tissue stem cells and how do they work?

Answer 5

• involved in the growth, repair and renewal of the cells found in that tissue
• they are multipotent
• as they can differentiate into all of the types of cell found in a particular tissue
• they have a narrower differentiation potential as some of the genes are already switched off

Question 6

which stem cells are pluripotent and what does it mean?

Answer 6

• embryonic stem cells

- they can differentiate into all the cell types that make up the organism

Question 7

which stem calls are multipotent and what does it mean?

Answer 7

• tissue stem cells

- they can differentiate into all of the types of cell found in a particular tissue type

Question 8

give two examples of the therapeutic uses of stem cells

Answer 8

the repair of damaged or diseased organs or tissues

• corneal repair
• regeneration of damaged skin

Question 9

How can stem cells be used in research?

Answer 9

• used as model cells to study how diseases develop and being used for drugs testing
• information on how cell processes such as cell growth, differentiation and gene regulation work

Question 10

what properties of embryonic stem cells make them useful for research purposes?

Answer 10

they can self-renew under the right conditions in a lab

Question 11

what are the ethical issues surrounding the use of embryonic stem cells for research?

Answer 11

• effective treatments for disease or injury

- but destruction of an embryo

Question 12

what is selective gene expression?

Answer 12

• every cell in your body has all the genes necessary for constructing the whole organism
• genes can be switched on or off when they are required
• so that the body isn’t wasting energy producing proteins in cells where they are not needed

Question 13

What is the therapeutic use of stem cells?

Answer 13

repair of damaged or diseased organs or tissues

Question 14

What are stem cells?

Answer 14

unspecialised cells in animals that can divide (self-renew) and/or differentiate