The percentage of juxtamedullary nephrons in kidneys is _______.

Options

A. 0.15
B. 0.45
C. 0.65
D. 0.85

Answer

To determine the percentage of juxtamedullary nephrons in the kidneys, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of Nephrons**:
- There are two main types of nephrons in the kidneys: cortical nephrons and juxtamedullary nephrons.
- Cortical nephrons are the most abundant, while juxtamedullary nephrons are less common.

2. **Identify the Percentage of Each Type**:
- It is known that approximately 85% of the nephrons in the kidneys are cortical nephrons.
- This implies that the remaining percentage must be juxtamedullary nephrons.

3. **Calculate the Percentage of Juxtamedullary Nephrons**:
- Since 85% are cortical nephrons, the percentage of juxtamedullary nephrons can be calculated as:
\[ 100\% - 85\% = 15\% \]

4. **Convert the Percentage to Decimal**:
- The decimal representation of 15% is 0.15.

5. **Select the Correct Option**:
- The options provided were 0.15, 0.45, 0.65, and 0.85. Based on our calculation, the correct answer is 0.15.

### Final Answer:
The percentage of juxtamedullary nephrons in kidneys is **0.15**.

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