Camel is different from other mammals in having

Options

A. Subcutaneous fat
B. No sweat glands
C. More than seven cervical vertebrae
D. Oval shaped R.B.C

Answer

### Step-by-Step Solution:

1. **Identify the Question**: The question asks how camels differ from other mammals.

2. **Understand Camel's Classification**: Camels belong to the class Mammalia, which is important for understanding their characteristics.

3. **Examine the Options**:
- **A. Subcutaneous fat**: Many mammals have subcutaneous fat for insulation and energy storage.
- **B. No sweat glands**: While camels have fewer sweat glands compared to some mammals, they do have them.
- **C. More than several cervical vertebrae**: Most mammals have a similar number of cervical vertebrae (usually seven).
- **D. Oval shaped RBC**: This is a unique characteristic of camels.

4. **Focus on the Unique Feature**: Among the options, the oval-shaped red blood cells (RBCs) of camels are distinct. Unlike most mammals, which have bi-concave disc-shaped RBCs that lack a nucleus, camel RBCs are oval and contain a nucleus.

5. **Explain the Significance**: The oval shape of camel RBCs allows them to flow better in dehydrated conditions. This adaptation helps them withstand high osmotic variations, which is crucial for their survival in arid environments.

6. **Conclude the Answer**: Based on the analysis, the correct answer is **D. Oval shaped RBC**.

### Final Answer:
Camel is different from other mammals in having **D. Oval shaped RBC**.

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