Differential stainability of a chromosome is called

Options

A. Heiroglyphics
B. Heteropycnosis
C. Heterosis
D. Idiogram

Answer

To answer the question "Differential stainability of a chromosome is called," we need to analyze the provided options and understand the terminology related to chromosomes.

### Step-by-Step Solution:

1. **Understanding the Question**: The question is asking for a term that describes the differential staining properties of chromosomes. This means we are looking for a specific characteristic of chromosomes that allows them to be stained differently based on their structure or composition.

2. **Evaluating the Options**:
- **Hieroglyphics**: This refers to an ancient writing system and is not related to chromosomes. **(Incorrect)**
- **Heterosis**: This term describes the phenomenon where hybrid offspring exhibit superior qualities compared to their parents, such as increased biomass and fertility. It does not relate to chromosome staining. **(Incorrect)**
- **Idiogram**: An idiogram is a diagrammatic representation of the chromosomes of an organism, showing their number and morphology, but it does not specifically refer to differential staining. **(Incorrect)**
- **Pyknosis**: This term refers to the condensation of chromatin in the nucleus, which can affect how chromosomes stain. This is the term that describes the differential stainability of chromosomes. **(Correct)**

3. **Conclusion**: The correct answer to the question is **Pyknosis**, as it refers to the differential stainability of chromosomes.

### Final Answer:
The differential stainability of a chromosome is called **Pyknosis**.