If plant height is controlled by 4 pairs of polygenes, maximum average height and minimum average height are 60 and 20 cm respectively. What will be the relative contribution of each polygene ?

Options

A. 5 cm
B. 20 cm
C. 40 cm
D. 25 cm

Answer

To solve the problem of determining the relative contribution of each polygene to plant height, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Maximum and Minimum Heights**:
- The maximum average height of the plants is given as 60 cm.
- The minimum average height of the plants is given as 20 cm.

2. **Calculate the Range of Height**:
- The range of height can be calculated by subtracting the minimum height from the maximum height.
\[ \text{Range} = \text{Maximum Height} - \text{Minimum Height} = 60 \, \text{cm} - 20 \, \text{cm} = 40 \, \text{cm} \]

3. **Determine the Number of Polygenes**:
- Since the question states that plant height is controlled by 4 pairs of polygenes, the total number of polygenes is:
\[ \text{Number of Polygenes} = 4 \, \text{pairs} \times 2 = 8 \, \text{polygenes} \]

4. **Calculate the Relative Contribution of Each Polygene**:
- The relative contribution of each polygene can be calculated by dividing the range of height by the number of polygenes.
\[ \text{Relative Contribution} = \frac{\text{Range}}{\text{Number of Polygenes}} = \frac{40 \, \text{cm}}{8} = 5 \, \text{cm} \]

5. **Conclude the Result**:
- Therefore, the relative contribution of each polygene to the plant height is 5 cm.

### Final Answer:
The relative contribution of each polygene is **5 cm**.

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