Question

data table: timing of cells in various stages of the cell cycle
stage of mitosis | # in field 1 | # cells in field 2 | # cells in field 3 | total # cells | time (for each phase) minutes | % of cell cycle
interphase | 3 | 12 | 8 | | |
prophase | 5 | 4 | 5 | 14 | 25 |
metaphase | 5 | 4 | 1 | 10 | 14.2 |
anaphase | 3 | 5 | 6 | 14 | 25 |
telophase | 8 | 3 | 3 | 14 | 25 |
totals | | | | 100 | 720 | 100%

Explanation:

Step1: Calculate % of Cell Cycle

The percentage of the cell cycle each stage takes is equal to the ratio of total cells in that stage to the total number of cells, multiplied by 100. Formula: $\% \text{ of Cell Cycle} = \frac{\text{Total # Cells in Stage}}{100} \times 100$

Step2: Verify time consistency

The total time for the cell cycle is 720 minutes, so the time for each stage should equal $\% \text{ of Cell Cycle} \times 7.2$ (since $720/100=7.2$), which matches the given time values.

Interphase:

$\% \text{ of Cell Cycle} = \frac{23}{100} \times 100 = 23\%$

Prophase:

$\% \text{ of Cell Cycle} = \frac{14}{100} \times 100 = 14\%$

Metaphase:

$\% \text{ of Cell Cycle} = \frac{20}{100} \times 100 = 20\%$

Anaphase:

$\% \text{ of Cell Cycle} = \frac{14}{100} \times 100 = 14\%$

Telophase:

$\% \text{ of Cell Cycle} = \frac{14}{100} \times 100 = 14\%$
(Note: There is a discrepancy in the total cells sum: $23+14+20+14+14=85$, not 100. Assuming the given total cells per stage are correct, we use them for the percentage calculation.)

Answer:

Stage of Mitosis	% of Cell Cycle
PROPHASE	14%
METAPHASE	20%
ANAPHASE	14%
TELOPHASE	14%

Note: The sum of total cells per stage (85) does not match the stated total of 100, indicating a potential error in the original data entry.