No virus can evolve to target mammalian red blood cells because of the

Options

A. small size with a biconcave shape
B. high concentration of oxygen
C. lack of aerobic pathway to generate ATP
D. lack of nuclear material

Answer

**Step-by-Step Solution:**

1. **Understanding Red Blood Cells**: Mammalian red blood cells (RBCs), also known as erythrocytes, are unique in that they lack a nucleus. This is a significant characteristic that differentiates them from many other cell types.

2. **Role of the Nucleus**: The nucleus in a cell contains genetic material (DNA) and is crucial for various cellular processes, including replication and the production of RNA. In cells with a nucleus, viruses typically hijack the host's cellular machinery to replicate their genetic material and produce new viral particles.

3. **Absence of DNA in RBCs**: Since mammalian RBCs do not have a nucleus, they also lack DNA. This absence of DNA means that there is no genetic material for a virus to use for replication.

4. **Implications for Viral Infection**: Without the ability to access DNA, a virus cannot replicate itself within the red blood cells. Viruses rely on the host's cellular machinery to produce RNA and replicate their genetic material. The lack of nuclear material in RBCs means that the virus cannot effectively take over the cell's machinery.

5. **Conclusion**: Therefore, the reason no virus can evolve to target mammalian red blood cells is due to the lack of nuclear material (DNA) in these cells. This absence prevents the virus from replicating and effectively infecting the RBCs.

**Final Answer**: No virus can evolve to target mammalian red blood cells because of the lack of nuclear material.

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