stem cells Flashcards
what is the difference between asymmetric and symmetric division
a
what is the niche and what does it do for a cell?
the niche is the environment that helps the cell retain its stem cell traits. during assymetric division, the cell is divided into one step one prolifereating cell, the stem cell stays in the niche and continues to do the stem related activities
how do you prevent a cell from differentiating
as long as Sox2 and Oct4 are around the cell will not differentiate. Sox 2 and Oct 4 are intrinsic and LIF and BMP both work to block the MAPK pathway
crypt of lebercun is an example of a
niche
what is an adult stem cell
undifferentiated stem cell found in diffrerentiated tissue. they can self renew and differentiate into all cell types in that specific tissue. (crypts)
what is a embryonic stem cell?
embryonic stem cell that came from a preimplatation embryo (5 days). can differentiate into a wide variety of cells
what are cancer stem cells?
cells that drive tumor formation and give rise to differentiated progeny
when is a cell considered to be differentiated?
when it has acquired specialized structure and function
what is the difference between pluripotent and totipotentn
they can both give rise to any tissue but totipotent is the only one that can still give rise to embryonic tisse. Pluropotent can only give rise to three germ layers. Totipotent is 8 cell stage.
multipotent-cells of the same fam
which factor is used to culture stem cells invitro?
LIF- leukemia inhibitory factor because it blocks the MAPk pathway
how are stem cells identified?
they use cell surface markers directed against specific membrane receptors. the most common is FACS- fluorescence activated cell sorting
what is the new cancer theory?
tumor cells arise from cells termed cancer stem cells that have properties of regular stem cells but cause cancer.
what explains cancer relapses after treatment?
the fact that there are cancer stem cells means you cannot kill them with chemo because they are not rapidly reporducing and they come back. Found in GLIOBLASTOMA
