The similarity between the the DNA and RNA molecules is that both of them are long polymers and they are made up of nucleotides.
The differences between the two molecules are as follows:
1. The sugar components of the DNA molecule are deoxyriboses while the sugar components of the RNA molecules are riboses.
2. The nitrogenous bases in DNA molecule are adenine, guanine, thymine and cytosine while the nitrogenous bases in the DNA molecule are adenine, guanine, uracil and cytosine.
3. The back bone of the DNA molecule is made of the deoxyriboses and phosphate while the back bone of the RNA molecule is made up of riboses and phosphate.
