🧬 Biology · Genetics
Mitosis and the Cell Cycle: true or false
Decide fast, then read the reason. Wrong answers are the best teachers, so every statement explains itself.
All statements and answers
Mitosis is the entire cell cycle.
✗ False. The cell cycle is interphase (G1, S and G2) plus M phase (mitosis and cytokinesis). Mitosis is only the nuclear division part of M phase.
Interphase is not a resting stage: the cell grows, does its job and copies its DNA.
✓ True. G1 and G2 are gaps in which the cell grows and works, and S phase is when the DNA is copied. Nothing about interphase is a rest.
A cat body cell has 38 chromosomes, so each daughter cell made by mitosis has 19.
✗ False. Mitosis keeps the chromosome number the same, so each daughter cell has 38. A number of 19 would come from meiosis, which makes egg and sperm cells.
Chromosomes are copied during prophase.
✗ False. DNA is copied in S phase of interphase. By prophase each chromosome already has two sister chromatids.
A plant cell builds a cell plate between its two new nuclei during cytokinesis.
✓ True. The stiff cell wall means a plant cell cannot pinch in two. Vesicles fuse to form a cell plate, which grows into a new wall between the daughter cells.
In metaphase, the sister chromatids are pulled to opposite ends of the cell.
✗ False. In metaphase the chromosomes line up in the middle of the cell. The sister chromatids are pulled apart in anaphase.
Cytokinesis can begin while mitosis is still finishing, in late anaphase or telophase.
✓ True. Cytokinesis is a separate process from nuclear division, but it overlaps the end of mitosis. That is why books differ on whether to list it as part of mitosis.
A garden pea body cell has 14 chromosomes in G1. At metaphase it has 14 chromatids.
✗ False. At metaphase each of the 14 chromosomes has two sister chromatids, so there are 28 chromatids. The number 14 is the chromosome count.
Some single-celled eukaryotes make new individuals by mitosis, which is a form of asexual reproduction.
✓ True. An amoeba, for example, divides by mitosis and cytokinesis into two cells that are genetically identical to the parent.
Bacteria divide by mitosis.
✗ False. Bacteria are prokaryotes, with no nucleus and no spindle. They divide by a simpler process called binary fission.
A replicated chromosome with two joined sister chromatids is still counted as one chromosome.
✓ True. You count chromosomes by counting centromeres, and the two sister chromatids share one centromere. They count as separate chromosomes only after they separate in anaphase.
The metaphase plate is a wall that forms across the middle of the cell.
✗ False. The metaphase plate is an imaginary plane where the chromosomes line up. A wall across the middle of a plant cell is the cell plate, which forms later in cytokinesis.
Two cells with identical DNA can become different cell types, such as skin cells and muscle cells.
✓ True. This is differentiation. Different genes are switched on in different cells, so cells with the same DNA can do different jobs.
Cancer is a group of diseases in which cells divide without the normal controls on division.
✓ True. Normal cells use controls, such as checkpoints, to decide when to divide. In cancer these controls are not working, so cells divide when they should not.