Stem cells Flashcards
Descibe the 5 stages of embryo development
1) 8 cell stage - cells all in external enviroment
2) Cell polaization - Cell seperates the inside from the outside
3) Compaction - the cells tighly bind together
4) inner apolar cut off: cells divide to create inner and outer cell masses
5) formation of blastocyte: inner cells become embryonic stem cells and outer cells become throphectoderm
What are the terms of differences in number of cells that a stem cell can divide to
Totipotent = all types, fertilised egg
Pluripotent = All types except trophectoderm, embryonic stemm cells
Multipotent = some cell types, adult stem cells
Terminally differentiated = one cell type
What cells never become terminally differentiated
Stem cells and gametes
Give an example of an adult stem cell and its division process
Haematopoitic cells = blood stem cells
Divide to give more stem cells and a progenator cell
progenator cells can then divide again until they differentate to their final product
How do cells differentiate
What are the three stages to this determination
Regulatory genes turn on transcription factor
this transcription factor will turn on the relivant transcription factors for the cell type.
these transcription factors activate other genes and therefore make proteins
Becomes terminally differentated, becomes a cell type
Stages:
Embryonic precurses
Fate determined cell
fully differentiated functional cell
What are the Different types of stem cells
Embryonic stem cells: pluripotent, on the innermass of bastocyte, can be cultured
Induced pluripotent stem cells: pluripotent
made from adult skin cells in a process called reprograming
Adult stem cells: Divide without limit, multipotent cells, types of cells formed depends on the type of tissue
Umbilical stem cell: Multipotent imature blood stem cells, can be used to cure blood disease
What are two key medicinal factors using stem cells
intergrative gene therapy
Regenerative medicine
Describe intergrative gene therapy
intergrative gene therapy alterations stay in the genome
Changing the genes of adult stem cells and intergrating them back into the body, all cells which dirrive from these will be change
Idea is to fix monogenetic dieases, with tools like crisper, can be inserted using a virus carrier
Describe Regenerative medicine
Use pluripotent cells to culture specific cell types using unique enviroements
Makes a whole organ or tissue type to be used to replace damaged tissues
What are the two cells which stem cells divide into
Stem cells
progenitor cells
How does intergrated gene therapy unitilize virus material
RNA copy of the desired gene edit is intergrated into the virus RNA
Infect the removed stem cells with the virus enabling the desired gene to be intergrated into the genome
Inserting the genetically altered cells back into the individual.
