Devision & Differentiation In Human Cells Flashcards
What are somatic cells
They are any body cell other than the cells involved in reproduction
How to stomatic cells devide
By mitosis
Why do stomatic cells devide
To form more somatic cells
What are germline cells
Gametes and the stem cells that make gametes
What does division by mitosis do in gremline cells
It maintains the diploid chromosome number - 23 homologous pairs
What does devision by meiosis do in germline cells
Produces 4 haploid gametes
What are the stages of meiosis
1) the chromosomes in the cell are copied (same as mitosis)
2) All the homologous chromosomes pair up
3) one from each pair move to opposite sides of the cell leading to 2 daughter cells being produced
4) each daughter cell then divides again by separating chromatids to form 4 cells . These 4 cells containing just 23 chromosomes
What is cell differentiation
The process by which a cell expressing certain genes to produce protein characteristics for that type of cell allowing the cell to carry out specialised functions
What are stem cells
Undifferentiated stomatic cells that can decide to either make copies of themselves or differentiate into specialised cells
What are the 2 types of stem cells
Embryonic stem cells and tissue (adult) stem cells
Whete to embryonic stem cells come from
Very early embryo
In embryonic stem cells what do they have the potential to do
All of the genes have the potential to be switched on so the cells can differentiate into almost any cell type
What are embryonic stem cells known as
Pluripotent
Where are tissue stem cells found
Found in tissue and bone marrow
What are tissue stem cells gene expression
Many of the genes are already switched off so they can only differentiate into a limited number of closely related to the tissue that they are found in
Or
Bone marrow can differentiate into different blood cells
What are tissue stem cells known as
Multi potent
What are tissue stem cells involved in
In the growth , repair and renewal of cells found in that tissue
What are the therapeutic used for steam cells
- the regeneration of damaged tissue and corneal repairs
What are the research uses of stem cells
- used as model cells
- provides information on how cell processes such as cell growth , differentiation and gene regulation work
What are the ethical issues of stem cells
Use of embryonic stem cells can offer effective treatments for disease and injury; however, it involved destruction of embryos
What are cancer cells
They are cells that devide excessively in an uncontrolled way
What do cancer cells not respond to
They don’t respond to regulatory signals and divide excessively
What is known as a tumour
A mass of abnormal/ cancer cells
What happens if cells within the tumour fail to attach to each other
They can spread throughout the body and form a secondary tumour
