Question

a student wants to modify model 1 so that it represents an rna double helix instead of a dna double helix. of the following possible changes, which would be most effective in making model 1 look more like rna than dna? a changing the sequence of the base pairs b changing the deoxyriboses to riboses by adding -oh groups c changing the shapes of the nitrogenous bases to match those shown in model 2 d changing the sugar - phosphate backbone to a ribbon, as shown in model 3

Explanation:

DNA contains deoxyribose sugar while RNA contains ribose sugar. The main structural difference between them is the presence of an -OH group in ribose which is absent in deoxyribose. Changing deoxyriboses to riboses by adding -OH groups would make the model more like RNA. Changing base - pair sequence doesn't distinguish between DNA and RNA as both can have various sequences. Changing the shape of nitrogenous bases or the sugar - phosphate backbone to a ribbon are not the key structural differences between DNA and RNA.

Answer:

B. Changing the deoxyriboses to riboses by adding -OH groups