Cell devision Flashcards
What is function of stem cells in plant meristems
They can differentiate into any cell required by the plant
What is the function of stem cells in adult bone marrow
Adult stem cells can differentiate into several cell types to replace dead or damaged cells
What is the function of stem cells in embryos
- Embryonic stem cells can replicate themselves and differentiate into other types of cells
- Embryonic stem cells may be able to treat conditions such as paralysis and diabetes by diving to replace damaged cells
What is a stem cell
An unspecialised cell which is capable of differentiating into other cell types.
Describe the second stage of the cell cycle
Each chromosome in a pair is pulled to opposite poles of the cell then the nucleus divides
Describe the third stage of the cell cycle
The cytoplasm and cell membrane divide - two identical daughter cells are produced
Describe first stage of the cell cycle
Longest stage - cell grow and increase in mass, replicate DNA and synthesise more organelles
e.g. Mitochondria and ribosomes
Why is mitosis important
- Produces identical cells which all have the same genetic information
- Produces additional cell for growth and repair
what are the 3 main stages of the cell cycle
1) Replication of DNA and synthesis of organelles
2) Mitosis
3) Division of cell
How are chromosomes arranged in the nucleus of a body cell
Arranged in pairs - 46 chromosomes form 23 pairs
How many chromosomes are found in the nucleus of gametes
23
How many chromosomes are found in the nucleus of human body cells
46
What are chromosomes made up of
Chromosomes consist of DNA molecules combined with proteins. They contain genes which provide instructions for protein synthesis
What is a gene
A section of DNA which codes for a protein
What is the function of stem cells in adult bone marrow
Adult stem cells can differentiate into several cell types to replace dead or damaged cells
