CELS 191 Lecture 26 Flashcards
(24 cards)
cells become more ______ and less _____ during development
specialised - flexible
what are totipotent cells
cells that can turn into any other kind of cell
an embryo begin as a small number of naive _____ cells
totipotent
embryonic stem cells (ICM) can give rise to all cell type except ___
trophectoderm (pluripotent)
what is a terminally differentiated cell
a cell that can only give rise to the same type of cell
all cells differentiate until they are terminally differentiated except…
stem cells and germ cells
what are the stages of embryonic development from 8 cell stage to blastocyst
- 8 cell stage
- cell polarisation
- compaction
- inner apolar cells cut off
- blastocyst
what do the polar cells become
trophectoderm (outside layer of the blastocyst)
what do apolar cell become
ICM - inner cellular mass
what are pluripotent cells
cells that can differentiate into lots of different types (not all) of cell in the body
at what point does a cells fate become determined - even if it hasn’t differentiated
once the master regulatory gene has been turned on
once the cells fate has been determined and the protein from the master regulatory gene has been produced what does it do
it turns on other cell (muscle for example) specific genes which cause the cell to differentiate
do differentiated cells contain all the DNA required to build an entirely new organism
yes
where as embryonic stem cells (ESCs) harvested from
the inner cell mass (ICM) of mammalian blastocyst embryos
are stem cell pluripotent or totipotent
pluripotent - they can develop into any of the 200 or so types of cells in our bodied given the right conditions
what are induced pluripotent stem cells
reprogrammed adult skin cells - iPSCs can be made from anyone and are genetically identical to the source skin cells
what can adult stem cells give rise to
more stem cells or cells which will go on to differentiate into one or more (but not all) types of functional tissue cells
why are umbilical cord stem cells kept frozen (banked)
the stem cells are multipotent, as they are immature blood stem cells they are less restricted than blood stem cells from adults
what can umbilical cord stem cells be used to treat
leukemias and many other blood diseases
why are blood stem cells important
tissues such as blood and skin need constant renewal
where are blood stem cells/haematopoetic stem cells found
in the bone marrow
what is the basis for integrate gene therapy
it may be possible to alter the genetic code of an individuals cells, it is proposed as a way of correcting single gene disorders - a normal allele could be inserted into the cells of affected tissue.
in integrative gene therapy how is the allele inserted into the cell
using virus - CRISPR can also be used
what is regenerative medicine
the idea that pluripotent stem cells can be used to repair or replace damaged organs or tissues. pluripotent stem cells can be made from skin cells or blood cells from a patient (genetically identical) to matched donors, or from embryos. these stem cells can be encouraged to differentiate into specific cell types which can be transplanted into patients
