Tobacco mosaic virus is a tubular filament of size

Options

A. 700*30nm
B. 300*10nm
C. 300*5nm
D. 300*18nm

Explanation

To answer the question regarding the size of the Tobacco Mosaic Virus (TMV), we can break it down into the following steps:

### Step-by-Step Solution:

1. **Identify the Virus**: The question refers to the Tobacco Mosaic Virus (TMV), which is known for its distinctive tubular filament structure.

2. **Determine the Size**: The size of the Tobacco Mosaic Virus is specified in terms of its dimensions. TMV has a length of 300 nanometers (nm) and a diameter (or breadth) of 18 nanometers (nm).

3. **Understand the Structure**: TMV has a rod-like helical structure. This means that the virus is not just a simple tube but has a specific arrangement of its components.

4. **Components of TMV**: The virus is composed of 2140 protein subunits that form its protective protein coat, known as the capsid.

5. **Genetic Material**: TMV is classified as a single-stranded RNA virus, meaning its genetic material is composed of a single strand of RNA.

6. **Impact on Plants**: TMV is known to cause mosaic disease in tobacco plants and other members of the Solanaceae family.

### Final Answer:
The Tobacco Mosaic Virus (TMV) is a tubular filament with a length of **300 nanometers** and a breadth of **18 nanometers**.

---