B2 Cell division Flashcards
What is the cell cycle
How cells duplicate and divide
What are the three stages of the cell cycle
Interphase
Mitosis
Cytokinesis
What happens during interphase
The cell grows
DNA duplicates
More organelles are made
What happens during mitosis
The genetic material separates to different ends of the cell and gets ready to divide into 2 separate daughter cells
What happens in cytokinesis
The cytoplasm and cell membrane split and 2 new identical cells are formed
What are stem cells
Cells that are undifferentiated
Give 5 examples of adult stem cells
Muscle cells-Divide
Nerve cells-Cannot divide
Red blood cells-cannot divide
skin cells-Cannot divide
bone marrow cells-Can divide to form all types of blood cell
Where does cell division occur in plants
Meristems- Found close to the tips of the roots and shoots
How are cells from meristems cloned
A tissue sample is scraped from a parent plant
The sample is placed in agar growth medium containing nutrients
The samples develop into plantlets that are then planted in compost
Advantages of plant cloning
Produces identical plants quickly and economically
Helps preserve rare species
Useful to provide crops that have desirable characteristics
Uses of human stem cells
Can be transplanted into patients to treat medical conditions and diseases or replace cells that have been damaged or destroyed
What is the benefit of using the patients stem cells in stem cell transplants
They are genetically identical so there is no risk of rejection
Donor cells in stem cell transplants
Would not be genetically identical
There would be fewer complications if cells came from close relative or a person with closely matched tissue type
What does therapeutic cloning produce
Stem cells with the same genetic makeup as the patient
What is the process of stem cell cloning
The nucleus is removed from a donor egg cell
The nucleus from the patients cell is placed into the empty egg cell
The cell is stimulated to divide
The cell develops into an embryo
After 4-5 days stem cells are removed
The stem cells are cultured for therapeutic use
