Division and differentiation of human cells Flashcards
what is the only form of division of a somatic cell?
Mitosis
What can adult stem cells in bone marrow differentiate into ?
Red blood cells, platelets, phagocytes and lymphocytes
what happens to mutations in somatic cells?
They are not passed onto offspring
After somatic cells divide by mitosis what different body tissue types do they differentiate into?
Epithelial, connective, muscle and nervous tissues
What happens to mutations in germline cells?
They can be passed on to offspring
What areas of research and therapeutic uses of stem cells are focused on?
The repair of damaged or diseased organs or tissues
Why are stem cells used as model cells?
To study how diseases develop or for drug testing
What does differentiation mean?
Changes to cells that allow them to specialise for different functions
Give two characteristics of human cancer cells
They don’t respond to regulatory signals and they divide repeatedly and excessively.
Describe one ethical dilemma related to the use of embryonic stem cells
To obtain embryonic stem cells the embryo must be killed but you must preserve life through medicine
What stem cell differentiate to replenish cells that need replaced?
Adult stem cell
Compare the processes of mitosis and meiosis
Mitosis has 1 division, 2 division in meiosis
Mitosis line up at the equator in single file, meiosis line up in pairs
Mitosis ends with diploid, meiosis end up hapliod
Mitosis ends with 2 cells, meiosis ends with 4 cells
What is a somatic cell?
Any cell in the body other than cells involved in reproduction
What is a germline cell?
They are gametes (sperm and egg) and the stem cells that divide to form gametes
What are the two divisions that chromosomes in the nucleus undergo?
Firstly homologous chromosomes and secondly separating chromatids
What does a cell express?
Certain genes to produces proteins characteristic for that type of cell.
What can genes in an embryonic stem cell do?
The genes can all be switched on so these cells can differentiate into any cell type
What can stem cells from the embryo do in the lab?
They can self-renew in the right conditions
What can stem cell research provide us information with?
Cell processes. Such as cell growth, differentiation and gene regulation
Examples of uses of stem cells
Skin grafts, drug testing and bone marrow transplant
What form of division can germline cells undergo?
mitosis and meiosis
What does division by mitosis of a germline stem cell do?
Maintains the diploid chromosome number
How many chromosomes does a haploid gametes have?
23
What are stem cells
They are unspecialised cells that can divide and can differentiate into specialised cells
What does division by meiosis produce?
haploid gametes
what are the two types of stem cells?
Adult and embryonic
What process does specialised cells arise through?
Differentiation and gene expression
How does a cell carry out specialised functions?
A cell expresses certain genes to produce proteins characteristic for that type of cell
What can cells in the very early embryo do?
Differentiate into all?
What are tissue stems cells involved in?
growth,repair and renewal
What is multipotent?
They can differentiate into all of the cell types found i a particular tissue type
blood stems cells located in bone marrow
What is pluripotent
become any cell type in the body. embryo
What is a tumour?
A mass of abnormal cells
What can happen to cells within a tumour?
They fail to attach to each other spreading through the body
What is mitosis?
Cell division that results in two daughter cells
They have the same number and kinds of chromosomes as the parent
What is meiosis?
Reduces the chromosome number by half, creating four haploid cells
What happens after a cell becomes specialised?
It stops dividing and only expresses the genes that are characteristic for that type of cell
