Mammlian RBC are `:-`

Options

A. Biconcave, circular, non Nucleated
B. Biconcave, Nucleated
C. Oval Nucleated
D. None

Answer

To answer the question "Mammalian RBC are:", we can break down the characteristics of mammalian red blood cells (RBCs) step by step.

### Step-by-Step Solution:

1. **Definition of RBCs**:
- RBCs, or red blood cells, are the cells responsible for transporting oxygen throughout the body.

2. **Shape of RBCs**:
- Mammalian RBCs are typically described as **biconcave**. This means they have a shape that is curved inward on both sides, resembling a doughnut without a hole.

3. **Size of RBCs**:
- They are relatively **small** in size, which allows them to efficiently navigate through the narrowest blood vessels, known as capillaries.

4. **Nucleus**:
- In mammals, mature RBCs are **non-nucleated**. This means that they do not contain a nucleus, which allows for more space to carry hemoglobin, the protein that binds oxygen.

5. **Overall Shape**:
- The overall shape can also be described as **circular** when viewed from above, but the biconcave structure is more significant for their function.

6. **Functionality**:
- The biconcave shape and lack of a nucleus enable RBCs to maximize their oxygen-carrying capacity and flexibility, allowing them to squeeze through capillaries.

### Final Answer:
Mammalian RBCs are **biconcave, small, circular, and non-nucleated**.

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