Presence of biconcave, circular and anucleated RBC is the characteristic feature of which animal?

Options

A. Ostrich
B. Whale
C. Crocodile
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks about the animal that has biconcave, circular, and anucleated red blood cells (RBCs).

2. **Identifying Key Features of RBCs:**
- Biconcave shape: This is a characteristic of certain RBCs, allowing for increased surface area for gas exchange.
- Anucleated: This means that the RBCs do not have a nucleus, which is a feature found in mature mammalian RBCs.

3. **Analyzing the Types of Animals:**
- Mammals: In mammals, the mature RBCs are typically biconcave and lack a nucleus.
- Birds (Aves): In birds, the RBCs are nucleated.
- Reptiles and Amphibians: Similar to birds, they also have nucleated RBCs.

4. **Considering the Options:**
- If the options include animals like birds (e.g., ostrich), reptiles (e.g., crocodile), and mammals (e.g., whale), we need to determine which of these has the characteristics described.
- The ostrich, being a bird, would have nucleated RBCs.
- The crocodile, being a reptile, would also have nucleated RBCs.
- The whale, being a mammal, would have biconcave and anucleated RBCs.

5. **Conclusion:** The animal that has biconcave, circular, and anucleated RBCs is the whale.

**Final Answer:** The whale.

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