Stem Cells Flashcards
What are stem cells?
They are undifferentiated cells that can continually divide and become specialised.
What are totipotent stem cells?
Stem cells that can divide and produce any type of body cell
Where can you get totipotent stem cells from?
From early mammalian stem cells - available for a very limited time
What are pluripotent stem cells?
Can be used to regrow damaged cells in humans as they can become almost every type of body cell
Where are pluripotent stem cells found?
Embryo - when it is in the form of a blastocyst
What are the issues with pluripotent stem cells?
They can continually divide and make tumours. Also, sometimes the treatment doesn’t work.
What can’t pluripotent stem cells specialise to form?
Placenta
What are the ethical issues surrounding stem cells?
There is a debate on whether it is right to make a therapeutic clone of yourself by making an embryo just to use the stem cells and then destorying that embryo.
Where are multipotent stem cells found?
found in mature mammals e.g. bone marrow
Where are unipotent stem cells found?
found in mature mammals
What stem cell can differentiate into a limited number of cells?
Multipotent stem cell
What stem cell can differentiate into only one (same) type of cell? Give an example:
Unipotent stem cell, so a muscle cell can only differentiate into more muscle cells
Which stem cells does the umbilical cord blood contain?
Multipotent
Which stem cells does the placenta contain?
Multipotent
Which stem cells does the embryo contain after 16 days of fertilisation?
Pluripotent
Which stem cells does the bone marrow contain?
Multipotent
What does iPS stand for?
Induced pluripotent stem cells
What makes a cell no longer specialised?
When all of the genes in that cell are turned on
What are induced pluripotent stem cells?
They are adult somatic (body) cells that have come from a volunteer and certain trancriptional factors are used to control the expression of certain genes - turning all of the genes on makes the cell unspecialised, it overcomes some of the ethical issues as there is no therapeutic cloning and no destruction of an embryo.
What are iPS cells created from?
Adult unipotent cells
The adult unipotent stem cells are altered to a state of …? In order to create iPS
pluripotency (state of pluripotency)
How do we switch on all of the genes in order to alter an adult unipotent cell to a state of pluripotency?
using transcriptional factors
What property do iPS cells have?
They have shown self-renewal propertiescan divide indefinitely to give limitless supplies.
