Mitosis and Meiosis Flashcards
What is the purpose of Mitosis?
To duplicate an existing cell and split, important in growth, healing and a pretty universal technique.
What are the four phases of the cell cycle?
1.M phase
2.G1 phase
3.S phase
4.G2 phase
Main functions of the phases?
G1-Required for cell growth and to double mass of proteins and organelles
S phase- DNA synthesis
G2-Between S and M phase.
Why are gap phases important?
Allow cell to grow and monitors conditions before commiting to S phase and mitosis
What happens during S phase
DNA replication and chromatin proteins
And activate proteins involved in DNA replication
What happens during M phase?
5 stages of mitosis and cytokinesis (cell div)
What are the stages of mitosis called?
Prophase
prometaphase
metaphase
Anaphase
Telophase
What can major events in external environment or other factors do in the cell cycle?
Can stop cell division at checkpoints
What do cancer cells do in cell cycle?
They ignore cell cycle control system and run the checkpoints
What happens during M phase?
Sister chromatids separated into identical daughter cells
What happens during prophase?
Replicated chromosomes condense
Centrosomes replicate and move apart and mitotic spindles form
What happens during prometaphase?
Nuclear envelope breaks down and the kinetocore of the chromosomes attach to spindle microtubules
Kinetocore is bonded to centromere of the chromosome
What happens during metaphase?
Chromosomes align between spindle poles and microtubules attach sister chromatids to whatever pole they are close to
What happens during anaphase?
Sister chromatids seperate as microtubules get shorter and spindle poles move apart pulling them to each pole
What happens during telophase
Daughter chromosomes arrive at poles and decondense and nuclear envelope forms on both ends of
End of mitosis