13. Stem cells

Question 1

What is fundamental to development?

Answer 1

Polarity

Question 2

What does epigenetic mean?

Answer 2

relating to or arising from non-genetic influences on gene expression

Question 3

What is haematopoiesis?

Answer 3

hematopoietic stem cell gives rise to different blood cells

Question 4

How are stem cell populations maintained?

Answer 4

Self-renewal

Question 5

What is asymmetric division?

Answer 5

a mitotic cell division that gives rise to progeny with different fate

Question 6

What happens if stem cells aren’t renewed?

Answer 6

Eventually there are no more stem cells and can’t generate more cell types from that pathway

Question 7

What does totipotent mean?

Answer 7

Can form whole new organism

Mammals: can form embryo, extraembryonic membrane & placenta

Question 8

what does pluripotent mean?

Answer 8

Can form many cell types but not all

Mammals: can form embryo

Question 9

What does multipotetent mean?

Answer 9

Can form fewer but still many cell types

Question 10

How do you Generating Embryonic Stem Cells? (3)

Answer 10

• ICM (inner cell mass) cells from blastocysts are required
• Put into tissue culture
• Become embryonic stem cells (ESCs)

Question 11

Are ESCs totipotent?

Answer 11

ESCs are not totipotent as cannot

generate all cells of the embryo

Question 12

What is blastocysts generated from?

Answer 12

Trophoectoderm

Question 13

What is the use of embryonic stem cells? (4)

Answer 13

• Can introduce genes into an organism to observe
• Can knockout endogenous genes to study its role
• Can perform Chromosomal rearrangements/deletion, allows you to generate disease models mimicking chromosomal defects in humans
• Can make specific genome edits, can remake mutations in gene know to cause disease

Question 14

What can a transgenic mouse be generated from?

Answer 14

Embryonic stem cells

Question 15

Why can Transgenic Mice be regenerated from Embryonic Stem Cells?

Answer 15

Embryo contained ICM from original embryo, plus the introduced ESCs

(it is a chimaera because it will have cells of two genotypes)

Question 16

What is used to Induce Pluripotent Stem Cells?

Answer 16

Multiple transcription factors

Question 17

What is the purpose of cell differentiation?

Answer 17

how cells acquire different fates

Question 18

What is the purpose of pattern formation?

Answer 18

how cells, tissues and organs are positioned

Question 19

What is the purpose of polarity?

Answer 19

often established early and encodes information