1.4 Cellular Differentiation Flashcards
Define a ‘Stem Cell’
A stem cell is an unspecialised cell that has the potential to become specialised or divide rapidly.
What are two things a stem cell can do?
- Differentiate
- Divide rapidly
Describe how a cell become specialised
The genes that code for proteins characteristic of that cell are ‘turned on’ while others that are not needed are ‘turned off’
This means the genes coding for characteristic proteins are expressed
What are lateral meristems responsible for?
Horizontal growth
What are apical meristems responsible for?
Lateral growth
a) Where are lateral meristems found?
b) Where are apical meristems found?
a) Found in the Cambium(between the xylem and the phloem)
b) Found in root and shoot tips
What are the two types of stem cells found in humans?
Adult and Embryonic
Where are stem cells found in the human body?
Developed tissues and in embryos
Describe the type of stem cell an embryonic stem cell is
Pluripotent - able to differentiate into any stem cell types
Compare the number of cells embryonic stem cells and adult stem cells can differentiate into
Embryonic stem cells - wide range
Adult stem cells - more limited range
Give a limitation of embryonic stem cells
They cannot self renew in vivo
State the two roles of tissue/adult stem cells
- Replace cells
- Growth of organism
- Repair cells
Give an example of a research use of stem cells
Research into how stem cells can differentiate
Used as model cells for testing of drugs
Give an example of a therapeutic use of stem cell
Help patients needing a bone marrow transplant (leukaemia patients)
What is an ethical considerations of using embryonic stem cells?
By using embryonic stem cells, some people believe you are killing a potential life
