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1. Forklare forskelle mellem RNA og DNA
Stryer, s.26-28
Devlin, s.78

There are 3 important differences between DNA and RNA: 

• RNA’s sugar component is ribose that has a 2`-OH group, while DNA has deoxyribose that has only –H atom in position 2`. The 2`-OH group makes RNA unstable because it becomes more susceptible to a base-catalysed hydrolysis. The removal of the 2`-OH group from ribose and replacement with 2`-H atom decreases the rate of hydrolysis by approximately 100-fold under neutral conditions and perhaps even more under extreme conditions.
   

• RNA contains uracil, while DNA contains thymine, which is a methylated uracil. The methylation facilitates the repair of damaged DNA.

(these two differences make DNA more suitable as genetic material)

• RNA molecules are usually one-stranded molecules, while DNA is double stranded. Thus, molar ratios (A+U) and (G+C) are not equal. In some viruses double stranded RNA can also be found.
   

• RNA has enzymatic activity and DNA doesn't
   

• DNA has permanent mutations, while if a mutation fx. happens in an mRNA molecule, only that mRNA and the protein that is translated from it are affected.

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