Outer most covering of chromosome is called :-

Options

A. Tonoplast
B. Pellicle
C. Unit membrane
D. Mesosome

Answer

To answer the question regarding the outermost covering of a chromosome, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the name of the outermost covering of a chromosome.

2. **Reviewing the Options**: We have four options to consider:
- A) Tonoplast
- B) Palicle
- C) Unit membrane
- D) Mesosome

3. **Analyzing Each Option**:
- **Option A: Tonoplast**: This is the membrane surrounding a vacuole in plant cells. It is not related to chromosomes. Therefore, this option is incorrect.

- **Option B: Palicle**: This is the correct answer. The palicle is a thin membrane that surrounds each chromosome and is composed of acromatic substance. This option is correct.

- **Option C: Unit Membrane**: This term generally refers to the basic structure of biological membranes but does not specifically refer to the outer covering of chromosomes. Thus, this option is incorrect.

- **Option D: Mesosome**: Mesosomes are infoldings of the plasma membrane found in bacteria and do not pertain to chromosomes. Therefore, this option is also incorrect.

4. **Conclusion**: After analyzing all the options, the correct answer is **B) Palicle**.

### Final Answer:
The outermost covering of a chromosome is called the **Palicle**.

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