Question Constellation Sign up for free AQA · GCSE · Biology · Higher
Fibre Attachment During Cell Division
Figure 9 shows some of the stages of cell division.
Some cancer drugs prevent cell division. Drug X prevents the fibres from attaching to the replicated chromosomes in stage 1.
Explain why a cell cannot complete division when affected by drug X.
Write your answer first. You can study the marking guidance whenever you need it.
Study the marking See what earns credit and compare it with a full-mark answer.
Marking points
- 1 Explains that unattached fibres cannot pull chromosomes to opposite ends of the cell.
- 2 Links this to failure of nuclear division or failure to form two genetically identical cells.
Full-mark answer
If the fibres cannot attach, they cannot pull the replicated chromosomes to opposite ends of the cell. The nucleus therefore cannot divide to produce two genetically identical daughter cells.
Why this answer loses marks
The cell cannot divide.
This repeats the outcome but omits how failed fibres prevent chromosomes moving and therefore block nuclear or cell division.