cellular differentiation and stem cells Flashcards
— is the process by which less specialised cell becomes more spezilized
cell diffrentaiton ( while cell division allow cell growth and the formation of 2 daughter cells and the morphogenesis controls the organised spatial distribution of cells )
cells can express different genes by —
differential gene expression in corder for cells to be different
true or false:
Differentiation is a common process in adults as well: adult
stem cells divide and create fully differentiated daughter
cells during tissue repair and normal cell turnover.
true
the 2 properties of stem cells are:
1- self renewal aka copying to form identical stem cells to maintain the stem cell pool
3- differentiation aka specialisation which replaces dead or damaged cells snd cant divide to make copies of themselves
— are undifferentiated cells that can divide and give rise to cells that can differentiate into specialised cells
stem cells
Microenvironment around stem cells that provides support and signals regulating self-renewal and differentiation is — and the types are:
- stem cell niches
2- direct contact
2- soluble factors
3- intermediate cells
stem cells are found in:
1- induced pluripotent cells
2- tissue stem cells as foetus , baby and throughout life
3- embryonic stem cells as blastocysts which is a very early embryo
—– measures how many types if spezlized cell a stem cell can make
potency
Can make multiple types of specialized cells, but not all types of —- are —-
mutlipotent , tissue stem cells , multipotent
Can make all types of specialized cells in the body. Lack potential to (extensively) contribute to extraembryonic
tissue, such as the placenta
Embryonic stem cells from ICM
pluripotent
Can make all types of cells in the body PLUS cells that are
needed during development of the embryo only: placenta,
umbilical cord
Early embryonic stem cells (8 cell stage embryo, morula)
totipotent
embryonic stem cells taken from inner cell mass is known as:
pluripotent and can make all possible types of spezilized cells as: nerons blood liver and skin
blood stem cells found in the bone marrow can —- and is —–
- only specialised types of blood cells and rbc white bc n platelet
—— cells can ONLY make the kinds of cell found in the tissue they belong to.
tissue stem cells ( mutlipotent) check slide 20
true or false: Self-renewal is division with maintenance of the differentiated state.
false , undifferentiated
HSC aka haematopoietic stem cells and MSCs are types of —– and are —-
- mutlipotent
- tissue stem cells
1- HSC can make nk cells m, T cells neutrophilcis , etc
2- MSC can make chrondotyrtes for cartilage , adipocyte for fat , and osteoblast for bone
—- uses genetic reprogramming to add centrain genes to the cells and we don’t have to destroy the embryo . Pros and cons include:
- induced pluripotent stem cells iPS cells
Advantage: No need for embryos
Genetically identical
Disadvantages: Large numbers of somatic cells needed
Long term studies still required.
adult cell from skin + genetic reprogramming by adding :Oct4, Sox2, Klf4 and c-Myc produces :
iPS and it differentiates into diff types 3
3 types of cloning are:
1- reproductive cloning: refers to make 2 identical individuals as dolly the sheep, difficult to do , illegal for humans
2- therapeutic cloning : experimental cloning use to make patients cell lines isolated from the embryo not intended for transfer in utero
3- molecular cloning : refers to the dna cloning and use to study what a gene does and its a routine in bio labs
— refers to the laboratory technique for creating a clone embryo with a
donor nucleus
somatic cell transfer SCT as in reproductive cloning:
which is basically taking an adult cell that contains dna and taking an off and we remove the nuclease and take the rest of it to produce a clone that’s identical to the one that gave the nuclease
—– is the transfer of nuclear material from a somatic cell into an enucleated
oocyte in the goal of deriving embryonic cell lines with the same genome as the nuclear donor.
-Little to no risk of rejecting transplanted cells/tissues
-immunologically
compatible with patient.
therapeutic cloning
application of stem cells include:
- Regenerative Medicine – Potential to treat diseases by
replacing cells which are irreversibly lost, and for which
there are currently no therapies,
– E.g. Parkinson’s, heart disease, diabetes, spinal cord injury…
– Bone marrow transplants and skin grafting are established
examples of therapeutic use of stem cells. - Drug testing and screening - stem cells directed to
produce a specific cell type in lab, huge amounts of
identical cells. At the early stages of candidate drug testing scientists need large number
of cells to carry out assays in vitro and replicate their experiments multiple times so they need
large numbers of identical cells. - Study disease processes - most cases its extremely
difficult to obtain cells damaged due to the disease in
order to study them in detail – diseased cells used to
model the disease.
true or false:
laws prohibit the creation of embryos for research + Ireland - one of few countries in Europe that has no regulation for stem cell
research.
true
extra info :
zygot —> morula —> blastocyte —> embryo —> foetus after 8th week –> us
