Final answer:
DNA and RNA both maximally absorb light at 260 nm, while proteins do so at 280 nm due to the aromatic amino acids content. The given answer choices contain a mistake as the correct absorbance values do not match any option exactly; the closest choice with a mistake is (A). It's essential to refer to scientific literature and calibrated equipment for exact measurements.
Step-by-step explanation:
The approximate wavelengths at which DNA, RNA, and proteins maximally absorb light are crucial for various biochemical assays, including those employing UV spectroscopy. DNA absorbs maximally at 260 nm, primarily due to its aromatic nucleobase content. Similarly, RNA also has a strong absorbance at 260 nm for the same reason. Proteins, on the contrary, show maximum absorbance at around 280 nm, mostly due to the presence of aromatic amino acids like tryptophan, tyrosine, and phenylalanine, which have absorbance peaks between 260 nm to 290 nm.
Therefore, the correct answer to the question, "At what approximate wavelengths do DNA, RNA, and proteins maximally absorb light?" is:
- DNA: 260 nm
- RNA: 260 nm
- Proteins: 280 nm
This corresponds to option (A) DNA: 260 nm, RNA: 280 nm, Proteins: 220 nm, where the values for RNA and proteins are incorrectly interchanged. The accurate answer is not explicitly provided in the given options, indicating there might be an error in the question. The accurate values, considering the scientific literature and equipment calibration standards, are DNA and RNA at 260 nm and proteins at 280 nm.