Cell Cycle Quiz
Questions: 16 · 10 minutes
1. At which stage of mitosis do sister chromatids normally separate and move toward opposite poles?
Prophase
Anaphase
Telophase
Metaphase
2. During which phase of the eukaryotic cell cycle is nuclear DNA replicated?
S phase
G1 phase
G2 phase
M phase
3. One chromosome remains unattached to spindle microtubules while the others are aligned. Which mechanism should delay the onset of anaphase?
The G1/S DNA-damage checkpoint
The cytokinetic contractile ring
The G2 checkpoint before mitosis begins
The spindle assembly checkpoint
4. Which event most directly defines cytokinesis?
The duplication of chromosomes
The division of the cytoplasm into two daughter cells
The rebuilding of nuclear envelopes around chromosome sets
The alignment of chromosomes at the cell equator
5. Microscopy shows that a cell's chromosomes have begun to condense while the mitotic spindle is starting to form. Which mitotic stage best fits these observations?
Anaphase
Cytokinesis
Telophase
Prophase
6. A drug prevents spindle microtubules from attaching properly to kinetochores. At which stage would many affected cells be expected to pause?
Metaphase
G1 phase
Telophase
Cytokinesis
7. An experimental mutation prevents cohesin proteins from being removed at the start of anaphase. What is the most direct expected result?
DNA replication begins again during mitosis
Chromosomes fail to condense during prophase
Sister chromatids fail to separate normally
The cell plate forms before chromosomes align
8. A mature cell exits the active cycle and remains metabolically active without preparing to divide. Which state best describes it?
G0
S phase
Metaphase
Cytokinesis
9. How do cyclin concentrations generally help regulate cell-cycle progression?
They remain constant and permanently activate every checkpoint
They rise and fall, helping activate cyclin-dependent kinases at appropriate times
They attach chromosomes directly to spindle microtubules
They copy DNA by serving as templates for DNA polymerase
10. Which sequence correctly shows the usual progression through the main phases of the cell cycle?
G1 → G2 → S → M
G2 → M → S → G1
S → G1 → M → G2
G1 → S → G2 → M
11. Compared with the same cell in G1, what is normally true after it completes S phase but before sister chromatids separate?
Its chromosome number and DNA amount have both been halved
Its chromosome number has doubled, but its DNA amount is unchanged
Its DNA amount has doubled, while its chromosome number is unchanged
Its DNA amount and chromosome number are both unchanged
12. A cell detects substantial DNA damage before DNA replication begins and pauses the cycle. Which regulatory point is most directly involved?
The metaphase-to-anaphase transition after chromatid separation
The spindle assembly checkpoint
The G1/S checkpoint
The cytokinesis completion point
13. What is the central outcome of mitosis in a typical somatic cell cycle?
The exchange of DNA between homologous chromosomes
The reduction of chromosome number by half
The replication of all nuclear DNA
The formation of two genetically similar daughter nuclei
14. A diploid cell has 8 chromosomes. At metaphase of mitosis, each chromosome consists of two sister chromatids. After normal mitosis, how many chromosomes should each daughter nucleus contain?
8
16
4
32
15. A dividing plant cell is completing cytokinesis. Which structure should form between its future daughter cells?
A cleavage furrow produced by a contractile ring
A new pair of centrosomes at the equator
A cell plate that develops into new separating walls
A metaphase plate made from aligned chromosomes
16. A cell has completed DNA replication, but its chromosomes have not yet visibly condensed for mitosis. Which phase is it most likely in?
G1 phase
G2 phase
S phase
Cytokinesis