The set of positively charged basic proteins is known a

Options

A. Histidine
B. DNA
C. RNA
D. Histones

Answer

To solve the question regarding the set of positively charged basic proteins, we can follow these steps:

### Step 1: Identify the Options
The options provided are histidine, DNA, RNA, and histones. We need to determine which of these is a set of positively charged basic proteins.

### Step 2: Understand the Characteristics of Each Option
- **Histidine**: This is an amino acid, but it is not a set of proteins.
- **DNA**: This is a nucleic acid that carries genetic information, and it is negatively charged due to its phosphate backbone.
- **RNA**: Similar to DNA, RNA is also a nucleic acid and is negatively charged.
- **Histones**: These are proteins that are positively charged and play a crucial role in packaging DNA in the nucleus.

### Step 3: Analyze the Properties of Histones
Histones are known for their positive charge because they contain basic amino acids such as lysine and arginine. This positive charge allows them to bind tightly to the negatively charged DNA, facilitating the formation of nucleosomes, which are the structural units of chromatin.

### Step 4: Conclusion
Based on the analysis, the set of positively charged basic proteins is known as **histones**. Therefore, the correct answer is option D.

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