L20 - stem cells

Question 1

define stem cell

Answer 1

pluripotent cell that can differentiate into any cell type

Question 2

define totipotent

Answer 2

can form any tissue / cell type / embryonic tissue

Question 3

define pluripotent

Answer 3

can form any of the 3 germ layers (and therefore any of the derivatives of them)

Question 4

define multipotent

Answer 4

cell that can give rise to cell types of specific tissues

Question 5

where do embryonic stem cells come from

Answer 5

inner cell mass of blastocyst (4-5 days old)

Question 6

what 2 things are stem cells capable of

Answer 6

self renewal

differentiation (daughter cells)

Question 7

are embryonic stem cells multi/pluri/totipotent

Answer 7

pluripotent

Question 8

self renewal is the _________ division of stem cells

Answer 8

symmetrical

Question 9

differentiation is the _________ division of stem cells

Answer 9

asymmetrical

Question 10

what is purpose of tissue stem cells

Answer 10

repair and maintenance in adult organisms

Question 11

when does the first stage of differentiation occur during embryonic development

Answer 11

morula stage

Question 12

what type are tissue stem cells

Answer 12

multipotent

Question 13

where are haematopoietic stem cells located

Answer 13

in bone marrow

Question 14

what is the function of haematopoietic stem cells (HSC)

Answer 14

can produce
1. lymphocytes
2. blood cells
(blood renewal)

Question 15

where are mesenchymal stem cells located

Answer 15

bone marrow
adipose tissue
umbilical cord

Question 16

function of mesenchymal stem cells

Answer 16

form

1. bones
2. cartilage
3. tendons
4. adipocytes

Question 17

what do patients have to be treated with before HSC can be collected and why

Answer 17

cytokines, they move stem cells from bone marrow to blood

Question 18

what is the function of neural stem cells

Answer 18

form new

1. neurons
2. astrocytes
3. oligodendrocytes

Question 19

how can stem cells be identified

Answer 19

1. able to differentiate

2. cells that proliferate for > 6 months without differentiating are pluripotent (long term self renewal)

Question 20

describe what is meant by stem cell niche

Answer 20

Microenvironment around stem cells that provides support and signals regulating self-renewal and differentiation
regulates SC behaviour

Question 21

how are induced pluripotent stem cells produced

Answer 21

1. somatic cell transduced with pluripotent factors (OCT4 , SOX2, KLF4 , cMYC )
2. produces IPSCs

Question 22

what are the yamanaka factors

Answer 22

pluripotent factors
OCT4
SOX2
KLF4
cMYC

Question 23

advantages of IPSCs?

Answer 23

1. more ethical than embryonic SCs

2. can be generated from any somatic cell

Question 24

applications of stem cells

Answer 24

1. treat blood diseases
2. make skin - treat burns
3. repair damaged cartilage / bone (mesenchymal SCs)

Question 25

what do embryonic stem cells express?

Answer 25

NANOG
OCT4
SOX2.

Question 26

what are stem cells found attached to

Answer 26

niche cells

Question 27

purpose of niche cells

Answer 27

prevent stem cells differentiating