Question

Why is DNA a better genetic material than RNA?

Answer 1

DNA is more stable than RNA .DNA has deoxiribose sugar with its double strands helixes make it a suitable genetic material. RNA plays role in protein synthesis, DNA is unique by all means. So DNA is perfect genetic material

Answer 2

DNA has lost a ‘hydroxyl group’ in its ‘ribose sugar’, as compared to RNA.  

This only difference makes DNA a favoured genetic material over RNA because:

i) DNA is more stable - RNA molecules have the hydroxyl group that is lost in DNA. This extra “oxygen and hydrogen” atoms makes RNA more prone to hydrolysis, i.e. RNA breakdown or degradation.

ii) Structural stability - The double helix structure of DNA is more stable and protects the DNA bases embedded inside the helix structure. RNA is a ‘single stranded molecule’ that is more prone to degradation.

iii) DNA repair and proofreading - DNA is equipped with better machinery for identifying base errors and correcting them and allows more chances and better facility for repair over RNA.