Question

which statement best describes how watson and crick’s model used other scientists’ work to create a model of dna?
they used chargaff’s rule to determine that it contains ribose sugar.
they used franklin’s photo to determine that dna was a double helix.
they used levene’s work to determine the number of base pairs in each strand.
they used nirenberg and matthei’s studies to determine that dna is made of nucleotides.

Explanation:

• Chargaff's rule relates to base pairing, not ribose sugar (DNA has deoxyribose).
• Rosalind Franklin's X-ray crystallography photo (Photo 51) provided critical evidence for DNA's double helix structure, which Watson and Crick used to build their model.
• Levene's work focused on nucleotide structure, not base pair counts per strand.
• Nirenberg and Matthaei's research centered on codons and protein synthesis, not DNA's nucleotide composition, and their work came after Watson and Crick's model.

Answer:

They used Franklin's photo to determine that DNA was a double helix.