W10 Stem Cells

Question 1

what are stem cells

Answer 1

unspecialised cells

Question 2

what do stem cells create as a middle step

Answer 2

intermediate cells

Question 3

what is lineage in terms of stem cells

Answer 3

number of cell types arising from a stem cell

Question 4

what is the potency of stem cells

Answer 4

possible routes for a stem cell

Question 5

where are totipotent cells found

Answer 5

zygotes
blastocytes
placenta

Question 6

where are pluri/multipotent cells found

Answer 6

embryonic stem cells

Question 7

how are cell types selected for

Answer 7

turning on and off genes

Question 8

how do radiation affect human cells

Answer 8

depleted blood and mutations

Question 9

what is the job of pluripotent stem cells

Answer 9

create all cell types

Question 10

what are pluripotent stem cells able to do

Answer 10

self renew

Question 11

what are Morphogens

Answer 11

signalling proteins which make gradients

Question 12

what are niche cells responsible for

Answer 12

creating microenvironments

Question 13

what happens when niche cell finds a signal

Answer 13

external polarity causes localization of cell fate determinants will undergo intrinsic asymmetry

Question 14

what are the 3 types of signals

Answer 14

autocrine
paracrine
systemic

Question 15

what is a autocrine signal for

Answer 15

signals for cells self

Question 16

what is a paracrine signal for

Answer 16

signals for neighbouring cells

Question 17

what is a systemic signals for

Answer 17

signals for other tissue

Question 18

what secretes signal molecules

Answer 18

ECM (extracellular matrix concentrates)

Question 19

what’s the job of the intestinal epithelium

Answer 19

regulates water and nutrient absorption

Question 20

how often does the intestinal epithelium renew

Answer 20

one of the fastest -> 3 to 5 days

Question 21

what are crypts in the intestinal epithelium for

Answer 21

contains intestinal stem cells and Paneth cells

Question 22

what type of receptors are found on intestinal crypts

Answer 22

G-protein receptors Lgr5

Question 23

what type of cell sheds into the lumen of intestines

Answer 23

differentiated cells

Question 24

how is apoptosis induced in cells

Answer 24

DNA damage signals
lack of growth stimuli

Question 25

what is flow cytometry and its steps

Answer 25

- identification of adult stell cells - dissociate tissue of interest into single cells - label stem cell with fluorescent antibody

Question 26

in vitro how are isolated cells form

Answer 26

in spheres

Question 27

in vitro how do you determine stemness of mini gut cells

Answer 27

- isolate crypt - embed in 3d matrix and use FACS - use EGF for growth and analysis

Question 28

what do Epidermal Growth Factor (EFG) do

Answer 28

Promotes cell proliferation

Question 29

how does a transplantation assay work in-vivo

Answer 29

irradiate tissue then add bone marrow cells from healthy donor

Question 30

how does cell lineage tracing work

Answer 30

- add visible genetic mark in stem cell - mark can be activated by specific tissue - track using a turnover assay

Question 31

how does nuclear transfer work for reprogramming diffed cells

Answer 31

- use oocytes or somatic cells - move nucleus into cytoplasm of large cell - changes in chromatin will occur

Question 32

how does cell fusion work for reprogramming diffed cells

Answer 32

- cell mass of blastocyst can be used to create ESC (embryonic stem cells) - 2 cells are fused - observe how the genomes interact

Question 33

how does transcription factor induced work for reprogramming diffed cells

Answer 33

- binding of a TF can cause growth of iPS cells

Question 34

how are iPS created

Answer 34

reprogramming from somatic cells

Question 35

why are iPS and ES useful for drugs

Answer 35

screening and human disease models

Question 36

describe nuclear reprogramming of reproductive cloning

Answer 36

- using somatic cells and oocytes using cell fusion - activate egg cell to turn somatic cell into totipotent cell

Question 37

what happens during asymmetric division

Answer 37

1 differentiated and 1 undifferentiated cell produced

Question 38

what is possible with symmetric division

Answer 38

2 un/differentiated cells

Question 39

what type of division do stem cells undego

Answer 39

symmetric division

Question 40

what type of cell uses asymmetric division

Answer 40

tissue cells

Question 41

what is retrospective experimental method for adult stem cell identification

Answer 41

using past models instead of prospective using raw collected data

Question 42

what are the 2 advantages of adult stem cells

Answer 42

- autologous - stable

Question 43

what is a disadvantage of adult stem cells

Answer 43

problems with amplification

Question 44

what are induced pluripotent stem cells

Answer 44

man made stem cells