DNA absorb `lambda_("max")`

Options

A. 600 Å (260 nm)
B. 7600 Å (760 nm)
C. 3900 Å (390 nm)
D. 3000 Å (300 nm)

Answer

To solve the question regarding the wavelength at which DNA absorbs light (lambda max), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Lambda Max**:
- Lambda max refers to the wavelength at which a substance exhibits the maximum absorption of light. This is important in biochemistry and molecular biology as it helps in identifying and quantifying substances like DNA.

2. **Identifying the Wavelength for DNA**:
- For DNA, the lambda max is known to be around 260 nanometers (nm). This is the wavelength where DNA absorbs ultraviolet (UV) light most effectively.

3. **Converting Wavelengths**:
- It is also useful to note that 1 nanometer (nm) is equal to 10 Angstroms (Å). Therefore, 260 nm can be converted to Angstroms:
- 260 nm = 260 x 10 Å = 2600 Å.

4. **Evaluating the Options**:
- Now, we look at the options provided:
- Option A: 600 Å, 260 nm
- Option B: 7600 Å, 760 nm
- Option C: 3900 Å, 390 nm
- Option D: 3000 Å, 300 nm
- The correct wavelength for DNA absorption is 260 nm, which corresponds to 2600 Å.

5. **Selecting the Correct Option**:
- Since option A states 600 Å, which is incorrect, and the correct value for DNA absorption is 260 nm (or 2600 Å), we can conclude that none of the options provided are correct as they do not match the known lambda max for DNA.

### Conclusion:
The correct answer is that DNA absorbs light at a wavelength of 260 nm (or 2600 Å), but this was not listed correctly in the options.