Select the incorrect statement about cortical nephrons.

Options

A. These are mainly concerned with urine concentration .
B. These have shorter of loop of Henle.
C. These do not have major role in Counter current mechanism.
D. These lack association with vasa recta .

Answer

To solve the question "Select the incorrect statement about cortical nephrons," we will analyze each statement provided in the options and determine which one is incorrect.

### Step-by-Step Solution:

1. **Understanding Cortical Nephrons**:
- Cortical nephrons are one of the two types of nephrons found in the kidneys, the other being juxtamedullary nephrons. They are primarily located in the cortex of the kidney.

2. **Analyzing the Statements**:
- **Statement 1**: "These are mainly concerned with the urine concentration."
- This statement is **incorrect**. Cortical nephrons have shorter loops of Henle and are not primarily responsible for concentrating urine; that role is mainly fulfilled by juxtamedullary nephrons.

- **Statement 2**: "These have short loop of Henle."
- This statement is **correct**. Cortical nephrons do have shorter loops of Henle compared to juxtamedullary nephrons.

- **Statement 3**: "These do not have a major role in the counter-current mechanism."
- This statement is **correct**. The counter-current mechanism is primarily associated with juxtamedullary nephrons, which have longer loops of Henle that help in creating a concentration gradient.

- **Statement 4**: "30 lakh association with Vasa Recta."
- This statement is **correct**. Cortical nephrons are associated with peritubular capillaries rather than the vasa recta, which are more associated with juxtamedullary nephrons.

3. **Conclusion**:
- The incorrect statement about cortical nephrons is **Statement 1**: "These are mainly concerned with the urine concentration."

### Final Answer:
The incorrect statement about cortical nephrons is **Statement 1**.

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