Division and differentiation in human cells Flashcards
What is a somatic cell
any cell in the body other than the cells involved in reproduction
What do somatic cells divide by
somatic cells divide my mitosis to form more somatic cells that form body tissues
What are germline cells
they include the stem cell that divide to form gametes and the gametes
What do germline cells divide by
mitosis and meiosis
What can the nucleus of a germline cell do
can divide my mitosis to maintain the diploid chromosome number
divide by meiosis to form haploid gametes
What is cellular differentiation
the process by whch a cell expresses certain genes to produce protein characteristic for that type of cell
What does cell differentitaion allow a cell to do
carry out specialised function
What are the types of stem cells
embryonic and tissue
Describe stem cells
they unspecialised cells
stem cells can divide to make copies of themselves
Describe cells in the very early embryo
they can differentiate into all the cell types that make up the individual so are pluripotent
Describe where tissue stem cells are found
throughout the tissues of the body e.g skin, bone marrow and small intestine
What are tissue stem cells involved in
the growth repair and renewal od the cells found in that tissue
How are tissue stems cell multipotent
they can differentiate into all of the types of cell found in a particular tissue type
are tissue stems cells multi or pluripotent
multipotent
Give an example of tissue stem cells being multipotent
blood stem cells located in the bone marrow can give rise to red blood cells
What are therapeutic uses of stem cells
stem cells can be used for the repair of damaged or diseased organs or tissues
Describe stem cell research
They can e used as model cells to study how diseases develop or for drug testing
stem cell research provides information on how cell processes such as cell growth, differentiation and gene regulation work
What is the ethical issue with stem cell research
the destruction of the human embryo when extracting the human embryonic stem cells
Why do cancer cells divide excessively
Because they do not respond to regulatory signals
When does cancer occur
when the control and regulation of cell division is damged or lost
What is a tumor
a mass of abnormal cells that are dividing out of control because they do not respond to regulatory signals
What happens in a benign tumour
the cells within the tumour remain attached to each other and can often be removed
What happens to cancer cells within a malignant tuour
they may fail to attach to each other and spread through the body to form secondary tumours
What can somatic cells divide by mitosis to form
more somatic cells
What cna germline stem ells divide by mitosis to produce
More germline stem cells
Name the type of stem cells that can be harvested from bone
tissue
Why does a muscle cell only produce the proteins typical of its cell type?
By expressing only the genes characteristic of that type of cell.
Explain how these secondary tumours occur
Cancer) cells fail to attach to each other and spread throughout the body
