3.8.2.1 Stem Cells (C20) Flashcards
What does totipotency mean?
can specialise into any type of cell including placenta, found in early stages of an embryo
What does pluripotency mean?
can specialise into most types of cells, but not form placenta, found in early embryos but not the earliest
What does multipotency mean?
can form some types of cells e.g. red and white blood cells, found in adult mammals
What does unipotency mean?
can only form one type of cell, found in adults
Cells that can specialise into any type of cell including placenta, found in early stages of an embryo are called…
Totipotent
Cells that can specialise into most types of cells, but not form placenta, found in early embryos but not the earliest are called…
Pluripotent
Cells that can can form some types of cells e.g. red and white blood cells, found in adult mammals are called…
Multipotent
Cells that can only form one type of cell, found in adults are called…
Unipotent
multicellular organisms are made up from…
many different types of specialised cells
specialised cells originated from..
stem cells
unspecialised cells that can develop into other cell types are called
stem cells
Two main sources of stem cells can be found..
in the embryo, adult tissues
these types of stem cells are only present in mammals in the first few divisions of the embryo
totipotent (very early embryo)
these types of stem cells are still found in the embryo but have lost their ability to develop into differentiate into placental cells
pluripotent
adult stem cells can be one of two types
- multipotent stem cells
2. unipotent stem cells
These types of stem cells can only differentiate into ONE type of cell
unipotent
these types of stem cells can differentiate into a limited number of stem cells e.g. bone marrow cells can form RBC and WBC
multipotent stem cells
Stem cells specialise because…
different genes are expressed (turned off and on)
Stem cells all contain the same genes - true or false?
true
Specialised cells all look different - why?
they all express different genes and thus proteins - this determines the cells overall structure
Which stem cell can red blood cells originate from?
bone marrow stem cells
Transcription is when
DNA is copied into mRNA
Translation is when
mRNA is translated into a sequence of amino acids
what are cardiomyocytes?
heart cells
what can stem cells be used for?
treat diseases e.g. paralysis - replace damaged cells/tissues
benefits of using stem cells in medicine?
save life and improve quality of life for many people
IPS cells stands for?
induced pluripotent stem cells
What are iPS cells?
created in the lab - reprogramming adult stem cells to become pluripotent
What are the limitations with adult stem cells?
limited differentiation capacity - they are mulitpotent
Where do we source embryonic stem cells from?
embryos created in the lab from IVF
Embryonic stem cells are classified as one of twp types
- totipotent (very early embryo)
2. pluripotent (early embryo)
Issue surrounding embryonic stem cells?
- ethics surrounding the sourcing of the embryos (embryo will be destroyed)
In all cells which genes will be permanently expressed?
Housekeeping genes e.g. genes involved in respiration
All organisms develop from a fertilised egg - what is the scientific name for this?
zygote
Zygotes divide by what process?
Mitosis
