The cell cycle of a root-tip cell in Vicia faba (broad bean) is estimated to be 15 h15\text{ h}15 h.
A student prepared a root-tip squash and observed it under a light microscope. Out of a total of 265265265 cells counted in the field of view, 383838 cells were found to be actively undergoing mitosis.
Explain why the meristematic tissue at the very tip of the root is selected for this investigation rather than cells from the zone of elongation.
Calculate the mean length of time a cell spends undergoing mitosis. Give your answer in minutes, correct to 3 significant figures.
Progression through the eukaryotic cell cycle is highly regulated by various molecular checkpoints.
Identify the specific phase of interphase during which semi-conservative DNA replication occurs.
Name the checkpoint that checks for correct chromosome alignment and spindle attachment before the cell enters anaphase.
If a cell is flagged with irreversible damage during checkpoint assessment, it may exit the active cell cycle into a non-dividing state, or undergo programmed cell suicide. State the designation of this non-dividing phase and the biological term for programmed cell death.
