(a) State the ‘Central dogma’ as proposed by Francis Crick. (5 marks)
Are there any exceptions to it ? Support your answer with
a reason and an example.
(b) Explain how the biochemical characterisation (nature)
of ‘Transforming Principle’ was determined, which was not
defined from Griffith’s experiments.
Yes , in some viruses flow of information is in reverse direction / reverse transcription = ½ + ½
e.g. Any Retrovirus / HIV = ½
(b) Protein and DNA and RNA were purified from heat killed S strain / smooth
Streptococcus / Diplococcus pneumoniae = ½
Protein + Protease transformation occured (R cell to S type) =½
RNA + RNA ase transformation occured (R cell to S type) =½
DNA + DNA ase transformation inhibited = ½
Hence DNA alone is the transforming material = ½