Constitutive heterchromatin is

Options

A. Condensed chromatin
B. present in all cells
C. Made of repetitve bases
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding Constitutive Heterochromatin**:
- Constitutive heterochromatin is a type of chromatin that is consistently present in all cells. It is a form of chromatin that remains condensed and is not actively involved in gene expression.

2. **Characteristics of Constitutive Heterochromatin**:
- It is characterized by being darkly stained under a microscope, indicating its condensed nature.
- It consists of repetitive DNA sequences, which means that the base pairs in this region repeat multiple times.

3. **Analyzing the Options**:
- The options provided are:
a) Condensed chromatin present in all cells made of repetitive bases
b) All of the above
- Since constitutive heterochromatin is indeed condensed, present in all cells, and made of repetitive bases, we can conclude that all statements are true.

4. **Conclusion**:
- Therefore, the correct answer is option 4: "All of the above."