Medullary nephrons are

Options

A. without Henle loop
B. without vasa recta
C. with long Henle loop
D. with less blood supply

Answer

**Step-by-Step Solution:**

1. **Understanding Medullary Nephrons**: Medullary nephrons, also known as intramedullary nephrons, are a type of nephron found in the kidneys of birds and mammals. They are characterized by their location and structure.

2. **Identifying Key Features**: One of the key features of medullary nephrons is the presence of a long loop of Henle. This structure is crucial for the concentration of urine, as it allows for the reabsorption of water and solutes.

3. **Analyzing the Options**:
- **Option A**: "Without Henle's loop" - This is incorrect because medullary nephrons do have a Henle's loop.
- **Option B**: "Without Vasarekta" - This is also incorrect since vasa recta, which are blood vessels that supply the nephron, are present.
- **Option C**: "With long Henle loop" - This is correct. Medullary nephrons are characterized by having a long loop of Henle.
- **Option D**: "With less blood supply" - This is incorrect as medullary nephrons have a high blood supply.

4. **Conclusion**: After evaluating all the options, the correct answer is **Option C**, which states that medullary nephrons are "with long Henle loop".

---