mitosis

What is interphase?

• occurs before mitosis

• G1 phase →cells grow and organelles are duplicated

• S phase → DNA is replicated

• G2 phase → the cell checks the duplicated chromosomes for error, making any needed repairs

What happens in prophase?

• chromosomes condense and they are visible

• nucleolus and nuclear envelope break down

• protein called tubulin forms spindle fibre which attach to centromere and move chromosome to centre of cell

What happens in metaphase?

• spindle forms

• chromatids are lined up at the centre of cell

What happens in anaphase?

• centromere divides into 2 and spindle shortens

• motor proteins walk across spindle in opposite directions so chromatids are pulled to opposite poles

• (requires ATP)

What happens in telophase?

• chromosomes reach poles of cell

• nucleolus and nuclear envelope reform

• spindle disintegrates

What is cytokinesis?

• After mitosis, cytokinesis occurs where 2 genetically identical diploid cells are produced