Bacterial viruses usually have

Options

A. ss RNA
B. ds RNA
C. ss DNA
D. ds DNA

Answer

**Step-by-Step Text Solution:**

1. **Understanding Bacterial Viruses**: Bacterial viruses are specifically known as bacteriophages. They are viruses that infect bacteria.

2. **Types of Genetic Material in Viruses**: Viruses can have different types of genetic material. The two main types are DNA and RNA. Each of these can be further classified as single-stranded or double-stranded.

3. **Focus on Bacteriophages**: When considering bacteriophages, the majority of them contain double-stranded DNA (dsDNA) as their genetic material. This is a key characteristic of most bacteriophages.

4. **Exceptions**: While most bacteriophages have double-stranded DNA, there are exceptions. For example, the QB bacteriophage is an RNA virus. However, this is not the norm for bacteriophages.

5. **Conclusion**: Based on the information, the correct answer to the question "Bacterial viruses usually have" is that they usually have double-stranded DNA.

**Final Answer**: Bacterial viruses usually have double-stranded DNA.

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