Why DNA is preferred Genetic Material

Genetic material should be capable of:

1. Stability: storing genetic information, chemical & Structural stability
2. Expression: able to express in from of traits or 'Mendelian Characters'
3. Replication: Be able to duplicate genetic material accurately
4. Inheritance: pass on copies of genetic information to next generation 
5. Evolution: allow production of variations through mutation or recombination

DNA vs RNA as genetic material

Both DNA and RNA have ability to act as genetic material but RNA preferred because:

1. DNA has Deoxyribose while RNA has Ribose - Chemical stability
2. Thymine in DNA while Uracil In RNA - Chemical stability

Chemically less reactive

➤Stability proved by Transformation (Griffith's experiment)

1. DNA double stranded, RNA single stranded - structural stability
   
2. Ability to replicate: complementary base pairing in dsDNA allows accurate copying during semiconservative replication 

Both DNA & RNA can express themselves through proteins. In fact protein synthesis cannot occur without RNA.

Ability to undergo mutation: both DNA & RNA able to mutate. In fact RNA mutates faster than DNA.

RNA being more reactive, and DNA being more stable; DNA was preferred over RNA as genetic material.

Now having read the topic try answering these questions:

1. Why is RNA more suitable in a catalytic role?
2. It is difficult to develop vaccines against RNA viruses s/a Rhinovirus (common cold Virus) or HIV?  
3. Justify, RNA is better suited for transmission of genetic information.