Unit 1.1 - Division And Differentiation In Human Cells Flashcards
What groups can cells be put into?
cells may be grouped into stomatic cells germline cells and stem cells.
Describe somatic cells.
somatic cells are non sex cells containing a diploid (two sets) number of chromosomes they divide by mitosis to form more somatic cells.
Explain cellular differentiation in somatic cells.
Initially cells are unspecialized with differentiate to become specialised in structure and biochemical properties. Differentiation happens as a result of the cell expressing the genes that are characteristic to that type of cell. Once a cell becomes differentiated it will only express these types of genes.
Give an example of a cell only expressing these types of genes.
For example the gene for the production of the oxygen carrying protein haemoglobin will only be expressed in red blood cells. Although all cells will possess this gene it will not be expressed i.e “switched on” and this is why these cells do not produce haemoglobin.
Describe stem cells.
Stem cells are unspecialised somatic cells that can divide to make copies of themselves (self renew) and differentiate into specialised cells.
Describe adult stem cells and how they are used.
tissue (adult) stem cells are involved in the growth, repair and renewal of the cells found within that particular tissue. They are multi potent. This means that they have the ability to make all cell types found in a particular tissue type.
Give example on when adult stem cells would be used.
for example blood stem cells in bone marrow can make all of the types of blood cells (red blood cells, platelets, phagocytes and lymphocytes) that are found in our blood.
Describe embryonic stem cells and when they would be used.
The inner cells of an early embryo (blastocyst stage) are able to make nearly all of the cell types in the body they are described as being pluripotent this is because most of the genes are still switched on or expressed these cells can self renew in a lab under the right conditions scientist call them embryonic stem cells.
Name the main body tissue types in our body.
The main body tissue types in our body are epithelial, connective, muscle and nerve tissue. Epithelial cells cover the body surface and line body cavities (bladder, windpipe etc) Somatic cells form different types of body tissue.
Name connective tissues.
connective tissues include blood, bone and cartilage cells. Muscle cells from muscle tissue and nerve cells from nerve tissue. The body organs are formed from a variety of these tissues.
Describe germline cells.
germline cells are diploid in humans they are called gamete mother cells.
How will a germline cell divide?
The nucleus of a germline cell divide by mitosis to produce more diploid germline cells or meiosis to produce haploid gametes.
What do gamete mother cells make-up?
Ovary and testie wall.
What will happen if a mutation occurs in germline cells? and somatic cells?
Mutations that occur in germline cells will be passed onto the Offspring where as mutations in somatic cells will not be passed onto offspring.
What does stem research provide?
Stem cell research provides information on how cell processes such as cell growth, differentiation and gene regulation work. Stem cells can also be used as model cells to study how diseases develop or for drug testing.
