Mitosis

This 3D model follows one cell through prophase, metaphase, anaphase, telophase and cytokinesis. The cell has 4 chromosomes, drawn in red and blue to show the two homologues of each pair, and each chromosome becomes two sister chromatids after replication. The Stage slider lets students pause on any moment, Auto-play loops the whole division, and the spindle can be shown or hidden. Readouts give the stage name, DNA per cell, chromosome count and a short description, which makes it handy for sequencing and explaining why daughter cells are identical.

• Drag the Stage slider slowly and read the What happens line for each stage.
• Stop at metaphase and see how the chromosomes line up across the middle of the cell.
• Compare the Chromosomes readout before and after anaphase to see the count double briefly.
• Hide Spindle fibres and predict what the cell would lose without them.
• Turn on Auto-play and call out each stage name before the readout changes.

1. 1Put the stages of mitosis in the correct order and describe each one.
2. 2Explain how sister chromatids separate so each daughter gets a full set of chromosomes.
3. 3Describe the role of the spindle in lining up and pulling apart chromosomes.
4. 4Conclude that mitosis produces two genetically identical cells.

Questions teachers ask