The number of root hairs on Dittmer's four month old Rye plant was

Options

A. 14 million
B. 1.4 million
C. 1.4 billion
D. 14 billion.

Answer

To solve the question regarding the number of root hairs on Dittmer's four-month-old rye plant, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Importance of Root Hairs**:
- Root hairs are crucial for the absorption of water and minerals from the soil. They are slender outgrowths of epidermal cells and are found in the region of cell differentiation in roots.

2. **Identify the Source of Information**:
- The question references a specific study conducted by a scientist named Dittmer in 1937, who estimated the number of root hairs on a four-month-old rye plant.

3. **Recall the Findings of Dittmer's Experiment**:
- According to Dittmer's research, the estimated number of root hairs on a four-month-old rye plant was found to be 14 billion.

4. **Evaluate the Given Options**:
- The options provided are:
- A) 14 million
- B) 1.4 million
- C) 1.4 billion
- D) 14 billion
- Based on Dittmer's findings, the correct answer is D) 14 billion.

5. **Conclude the Answer**:
- Therefore, the number of root hairs on Dittmer's four-month-old rye plant is 14 billion.

### Final Answer:
The number of root hairs on Dittmer's four-month-old rye plant was **14 billion**.

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