Term heterochromatin and euchromatin were first coined by :–

Options

A. Heitz
B. Balbiani
C. Painter
D. Kostoff

Answer

To solve the question "Term heterochromatin and euchromatin were first coined by:", we can follow these steps:

### Step 1: Understand the Terms
- **Heterochromatin** refers to the densely packed form of DNA, which is transcriptionally inactive and appears darker under a microscope.
- **Euchromatin** is the less condensed form of DNA that is transcriptionally active and appears lighter under a microscope.

### Step 2: Identify the Options
- The question provides multiple options, and we need to identify which scientist first coined the terms.

### Step 3: Evaluate Each Option
1. **Hits**: This option is correct. Emil H. Hitts introduced the terms heterochromatin and euchromatin in 1928.
2. **Palpiani**: This option is incorrect. Palpiani is known for discovering palatine chromosomes, not for the terms in question.
3. **Painter**: This option is also incorrect. Painter contributed to genetics but did not coin these terms.
4. **Cost of**: This option is incorrect as well. There is no significant contribution related to these terms by this scientist.

### Step 4: Conclusion
Based on the evaluation of the options, the correct answer is **Hits**.

### Final Answer
The term heterochromatin and euchromatin were first coined by **Emil H. Hitts**.

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