Mitosis Flashcards
What percentage of the cell cycle is interphase
90 percent
What are the different parts to the cell cycle, in order?
G1, S phase, G2 (G0 not part of the order) - interphase
M phase - mitosis
What happens at G1 (gap 1)
1st growth phase
Proteins are synthesised
What happens at G0 (gap 0)
Resting phase
Can be temporary or permanent
Cells stay in the loop and go round and round
Why does G0 occur
Happens when conditions aren’t optimum for division or when the cell is fully differentiated
What happens at S phase (DNA synthesis)
Synthesis phase
DNA is replicated
What happens at G2 (gap 2)
2nd growth phase
Organelles grow, divide and energy stores increase
What happens at interphase
DNA replicates as cell prepares to go through mitosis
What is not visible in interphase
Chromosomes
What are the 4 phases of mitosis
Prophase
Metaphase
Anaphase
Telophase
PMAT
What happens at prophase
Chromosomes become visible
Two chromatids are joined by a centromere
The nuclear envelope disintegrates
Nucleolus disappears and spindle fibres form
What happens at metaphase
Chromosomes line up along the equator of the cell attached by their centromeres to the spindle fibres
What happens at anaphase
Each chromatid splits at the centromere
The chromatids are pulled apart to opposite poles by the spindle fibres
What happens at telophase
Chromatids reach poles
Nuclear envelope and nucleolus reforms
Spindle fibres disintergrate and the cytoplasm divides
What happens at cytokinesis
Cell constricts in the middle and the two daughter cells will form
