Which property of DNA prevents it to enter a cell through the cell membrane?

Options

A. Negative charge
B. Hydrophilic
C. Both (1) and (2)
D. Hydrophobic

Answer

To answer the question "Which property of DNA prevents it from entering a cell through the cell membrane?", we can analyze the properties of DNA in relation to the structure of the cell membrane. Here is a step-by-step solution:

### Step-by-Step Solution:

1. **Understanding DNA Structure**:
- DNA (Deoxyribonucleic Acid) is a large, complex molecule made up of nucleotides. It has a negatively charged phosphate backbone.

**Hint**: Recall that DNA is a polymer made of repeating units called nucleotides.

2. **Cell Membrane Composition**:
- The cell membrane is primarily composed of a phospholipid bilayer, which has hydrophobic (water-repelling) tails and hydrophilic (water-attracting) heads.

**Hint**: Think about the structure of the cell membrane and how it interacts with different molecules.

3. **Charge of DNA**:
- DNA is negatively charged due to its phosphate groups. While this charge can affect interactions with other molecules, it does not solely determine whether DNA can pass through the cell membrane.

**Hint**: Consider how charge affects molecular interactions with the cell membrane.

4. **Hydrophilic Nature of DNA**:
- DNA is hydrophilic, meaning it is attracted to water. The hydrophilic nature of DNA makes it incompatible with the hydrophobic environment of the cell membrane.

**Hint**: Remember that hydrophilic substances generally do not pass through hydrophobic barriers easily.

5. **Conclusion**:
- The property of DNA that prevents it from entering a cell through the cell membrane is its hydrophilic nature. The hydrophobic nature of the cell membrane acts as a barrier to hydrophilic substances like DNA.

**Final Answer**: The property of DNA that prevents it from entering a cell through the cell membrane is its hydrophilic nature.

### Summary:
The hydrophilic nature of DNA prevents it from passing through the hydrophobic cell membrane, making it unable to enter the cell.