1.1 - Differentiation And Stem Cells Flashcards
What is differentiation controlled by?
Differentiation is controlled by the switching on/off of genes which produce proteins characteristic for that cell.
What are stem cells?
Stem cells are unspecialised cells which can divide to make copies of themselves or become specialised cells.
What are the two types of stem cells?
Embryonic and Adult Tissue
Where are embryonic stem cells found?
Inside a blastocyst
Where are adult tissue cells found?
Inside bone marrow
Embryonic stem cells are “pluripotent”.
What does this mean?
They are able to develop into any type of specialised cell
Adult Tissue cells are “multipotent”.
What does this mean?
They can only develop into a limited range of cells
What are somatic cells?
Somatic cells are non-sex cells (body cells) and contain two sets of chromosomes (diploid).
Examples of somatic cells and their functions:
- nerve cells form nervous tissue
- muscle cells form muscle tissue
- epithelial cells cover the bodies surface and line body cavities
- blood, cartilage and bone cells form connective tissue
What are germline cells?
Germline cells are diploid cells that can:
- divide by MITOSIS to produce more germline cells
- divide by MEIOSIS to produce haploid gametes
What are the therapeutic uses of stem cells?
- bone marrow transplants
- skin grafts (for burns)
- repair of damaged or diseased organs (eg. Corneal transplant)
What are cancer cells?
Abnormal cells that do not respond to regulatory signals and divide excessively to produce a mass of abnormal cells (a tumour).
How is a secondary tumour formed?
If cancer cells fail to attach to each other they spread throughout the body
What is differentiation?
Differentiation is the process by which unspecialised cells can develop more specialised functions.
