Flashcards in 3.8.2 Gene expression and cancer Deck (123)
Totipotent stem cells are able to differentiate into..
any type of body cell
multicellular organisms are made up from...
many different types of specialised cells
specialised cells originated from..
unspecialised cells that can develop into other cell types are called
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
adult stem cells can be one of two types
1. multipotent stem cells
2. unipotent stem cells
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
These types of stem cells can only differentiate into ONE type of cell
Stem cells specialise because...
different genes are expressed (turned off and on)
All cells contain the same DNA - true or false?
Stem cells all contain the same genes - true or false?
Molecules which regulate the expression of genes are called..
Where do transcription factors bind to regulate gene expression?
upstream of the gene (promoter region)
What do transcription factors do to regulate gene expression?
encourage binding of RNA polymerase (turn on genes) or prevent RNA polymerase binding (turn off genes)
Where are transcription factors found?
When a cell receives a signal to express a gene what does the transcription factor do?
moves from the cytoplasm to the nucleus
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?
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