Cell and Nuclear Division · Paper 1 — Free Biology SL Practice Questions

A researcher applies colchicine to human liver cells undergoing mitosis. Colchicine prevents tubulin polymerisation, blocking spindle fibre formation. At which stage of mitosis will most cells become arrested?

A student uses a light microscope to examine two cells. In a cell from a growing onion root tip, individual chromosomes are aligned along the cell equator. In a cell from a developing lily anther, homologous pairs of chromosomes are aligned along the cell equator. Which row correctly identifies the stage and process occurring in each cell?