B2-Cell division Flashcards
What is a gene?
A short section of DNA that codes for a protein/controls a characteristic
What are chromosomes?
Structures in the nucleus that carry genes
Briefly describe the cell cycle
Cell content(including DNA) is replicated, mitosis occurs to make 2 genetically identical cells
Define mitosis
Cell division that produces 2 genetically identical daughter cells
What type of reproduction is based only on mitosis?
Asexual
State 3 key importances of mitosis
Growth, repair, asexual reproduction
Briefly describe the 1st stage in the cell cycle
Cell size increase, DNA and organelle replication
Briefly describe the 2nd stage(mitosis) in the cell cycle
Cytoplasm and cell membrane divides into 2 daughter cells
What has to happen to the cell before mitosis to ensure that we can have 2 genetically identical daughter cells?
DNA and organelles must replicate before division
Define differentiation
The process where a cell becomes specialised/adapted to perform specific functions
Define stem cell
Undifferentiated cell with the potential to become specialised
Define adult stem cells
Stem cells that can only differentiate into a specific type of cell
Where does differentiation of stem cells occur in humans?
Bone marrow
Where does differentiation occur in plants?
Meristem/root tip/shoot tip
Define cloning
Production of identical offspring by asexual reproduction
By which cell division type does cloning occur?
Mitosis
Define zygote
The single new cell formed right after fusion of gametes
Define embryo
A ball of cells made from mitosis of zygote
Define embryonic stem cells
Stem cells from an early embryo that can differentiate into all cell types
Suggest 2 diseases that can be treated with stem cell treatment
Paralysis, diabetes, blindness
Briefly describe how we can use stem cells to treat someone with type 1 diabetes
Induce embryonic stem cells to produce healthy pancreas cells to make enough insulin
Where do you get stem cells in plants?
Meristem/Root tip/Shoot tip
Why is the ability to clone plants quickly a benefit?
Produce large numbers of rare plants reliably and safely to stop their extinction and for research, agriculture advances
State one medical/scientific benefit of therapeutic cloning.
No rejection problems
State one risk or concern people may have about using stem cells.
Unethical to use aborted embryos; difficult and expensive project; cancer concern; viral infection/transmission
