Part 3: Calculate the percentage of the cell cycle spent in each stage using the formula: Number of cells in given stage \div total number of cells counted \times 100 = % of the cell cycle spent in this stage.
| Stages | Number of cells (Copied from Part 1) | Percentage of Cell Cycle |
| ----------- | ------------------------------------- | ------------------------ |
| Interphase | 34 | |
| Prophase | 8 | |
| Metaphase | 3 | |
| Anaphase | 2 | |
| Telophase | 2 | |
| Cytokinesis | 1 | |
Answer (1)
Calculate the total number of cells: 34 + 8 + 3 + 2 + 2 + 1 = 50 .
Calculate the percentage for Interphase: 50 34 × 100 = 68% .
Calculate the percentage for Prophase: 50 8 × 100 = 16% .
Calculate the percentages for the remaining stages similarly, resulting in: Metaphase (6%), Anaphase (4%), Telophase (4%), and Cytokinesis (2%).
The percentage of the cell cycle spent in each stage is: I n t er p ha se : 68% , P ro p ha se : 16% , M e t a p ha se : 6% , A na p ha se : 4% , T e l o p ha se : 4% , C y t o kin es i s : 2% .
Explanation
Calculate the total number of cells First, we need to find the total number of cells counted. We sum the number of cells in each stage of the cell cycle: Interphase, Prophase, Metaphase, Anaphase, Telophase, and Cytokinesis.
Total number of cells The total number of cells is calculated as follows: T o t a l = 34 + 8 + 3 + 2 + 2 + 1 = 50 So, we have a total of 50 cells.
Formula for percentage calculation Next, we calculate the percentage of the cell cycle spent in each stage using the formula: P erce n t a g e = T o t a l e wl in e n u mb ere wl in eo f e wl in ece ll s N u mb ere wl in eo f e wl in ece ll se wl in e in e wl in es t a g e × 100
Calculate percentage for each stage Now, we calculate the percentage for each stage:
Interphase: P erce n t a g e I n t er p ha se = 50 34 × 100 = 68%
Prophase: P erce n t a g e P ro p ha se = 50 8 × 100 = 16%
Metaphase: P erce n t a g e M e t a p ha se = 50 3 × 100 = 6%
Anaphase: P erce n t a g e A na p ha se = 50 2 × 100 = 4%
Telophase: P erce n t a g e T e l o p ha se = 50 2 × 100 = 4%
Cytokinesis: P erce n t a g e C y t o kin es i s = 50 1 × 100 = 2%
Final Answer Therefore, the percentages of the cell cycle spent in each stage are as follows:
Interphase: 68%
Prophase: 16%
Metaphase: 6%
Anaphase: 4%
Telophase: 4%
Cytokinesis: 2%
Examples
Understanding the proportion of time cells spend in different stages of the cell cycle is crucial in cancer research. For example, if a cancer drug targets cells in a specific phase, knowing the percentage of cells in that phase helps predict the drug's effectiveness. If a large percentage of cells are in a phase targeted by the drug, the drug might be more effective at slowing down the cancer's growth. This type of calculation is also used in developmental biology to understand how tissues grow and develop.
