- I. Miescher: Correct. He was the first to identify and name a substance called nuclein, now known as DNA, from pus cells in 1869.
- II. Fisher: Incorrect. While Fisher contributed to biochemistry, he is not credited with isolating nucleic acids.
- III. Altman: Incorrect. Richard Altman is known for renaming nuclein as nucleic acid, not for discovering purines.
- IV. Franklin: Correct. Rosalind Franklin produced X-ray diffraction images of DNA, which played a crucial role in discovering the DNA double helix structure.
Therefore, the correct pairs are:
- Miescher — Named nuclein
- Franklin — DNA X-ray diffraction