Key Area 4: Cellular Differentiation Flashcards
What is cellular differentiation?
The process by which a cell expresses certain genes to produce proteins characteristic to the cell type.
What do cells undergo to become specialised?
Differentiation
What does differentiation adapt cells to do?
To carry out a particular function.
What are characteristics of cells that carry out specific functions?
They have specific shapes and biochemical pathways.
What can happen to genes depending on the function of a specialised cell?
They can be switched on or off.
What happens during differentiation?
Many genes remain switchen on; other genes necessary for the cell’s functions are switched on; and unnecessary genes are switched off.
What is a meristem?
Regions of unspecialised cells in plants that can self-renew and/or differentiate
What are the two main types of meristem?
Apical meristem, and lateral meristem.
Where can the apical meristem be found?
At the root and shoot tips.
Where can the lateral meristem be found?
Throughout the plant.
What do apical meristems give rise to?
Increase in plant length/height.
How do apical meristems increase plant length/height
Cells at root and shoot tips undergo repid mitosis and cell division, producing new cells. New cells then take in water by vacuolation and expand by elongation. New cells produced can then differentiate to form specialised tissue.
What is the other name given to lateral meristems?
Cambium.
Where can lateral meristems be found?
In vascular bundles between the xylem and phloem.
What do lateral meristems cause?
Thickening of the plant.
What do all sexually reproducing animals start out as?
A zygote.
What happens to the zygote?
It divides by mitosis and cell division to form an embryo.
How much of the genetic code does the zygote hold?
The entire genetic code.
What is the status of the genes in an embryo?
They are all switched on, or have the potential to be switched on.
How is an embryonic stem cell naturally altered genetically?
Genes are switched on and off at specific points in time and at particular points within the organism.
Which genes does a cell express once it has been differentiated?
The genes that code for the proteins specific to the workings of that particular cell.
What is a stem cell?
An unspecialised cell in animals that can self-renew and/or differentiate.
What are the different types of stem cell?
Embryonic and tissue.
How many cell types can embryonic stem cells differentiate into?
Due to them being pluripotent, they can divide into all cell types.
How many genes in an embryonic stem cell can be switched on?
All of them.
What are tissue stem cells involved in?
Growth, repair and renewal of cells.
What is the word given to tissue stem cells due to the fact that they can differentiate into all types of cell found in a tissue type?
Multipotent.
What are some therapeutic uses of stem cells?
Repair of damaged or diseased organs or tissues.
What are some research uses of stem cells?
They can be used as model cells to study how diseases develop or they can be used for drug testing.
What is the controversy around the use of embryonic stem cells?
They can offer effective treatments for disease and injury, however, it involves the destruction of emryos and the destruction of a potential life.
