stem cells and lineage Flashcards Preview

Y2: BL2301 > stem cells and lineage > Flashcards

Flashcards in stem cells and lineage Deck (23)
Loading flashcards...
1
Q

how do you go from a single cell to an organism

A

control in space and time

2
Q

what is differentiation

A

process by which a cell undergoes a change to an overtly specialised cell type

3
Q

what is specification

A

if you can isolate cells or tissues and they still form what they were originally meant to then their fate was already specified

4
Q

what is induction

A

process by which one embryonic region interacts with a second region to influence that second regions differentiation or behaviour

5
Q

where do induction signals come from

A

other cells or the environment

6
Q

what are three cell signalling mechanisms

A

dissusion
direct contact
gap junctions

7
Q

what is an example of induction

A

vegetal tissue induces mesoderm in animal cap

8
Q

what is determination

A

progressive restriction in developmental potential of different cell types

9
Q

what is competence

A

cells may be competent to receive signals only for a short time

10
Q

what is regulative development

A

also called indeterminate

is remaining cells can compensate for tissue loss

11
Q

what is mosaic development

A

also called determinate

seperation of blastomeres results in incomplete parts of embryos in development is usually arrested

12
Q

what are three ways that different lineages can arise from a common cell ancetsor

A

asymmetric inheritance
asymmetric cell division
timing and position are important

13
Q

what are 3 ways of asymmetric inheritance and name one exmaple

A

protein or rna
uneven distribution
inherent difference
the germ line

14
Q

why is timing so important for the arison of new lineage

A

early stages my be regulative but lineages can then become determines and invariatn

15
Q

describe long and short range signals pattern tissue

A

all multicellular organisms use the same pathways

16
Q

what are morphogens

A

exposure time or concentration differences caused by diffusion of inducer (morphogen) away from the source

17
Q

why is half life of morphogens important

A

protein degredation can be increased

as is the rate of diffusion- ECM can slow morphogens down

18
Q

what do morphogen gradients equal

A

differentiation differences

19
Q

what is lateral inhibition

A

can go on to act as signalling centers for further patterning

20
Q

describe notch signalling

A

transient asymmetry is enough

21
Q

describe positive feedback for notch signalling

A

asymmetry is self amplifying

22
Q

give an example of notch signalling

A

at first, contiguous neural plate cells express neurogin delta and notch
with time one cell expresses more delta, develops into a neuroblast and inhibits the neighbouring cells from following a neural fate

23
Q

what are two examples of how the same signal can induce different responses

A

combinatorial signalling

cell memory