Green and purple boxes for Nucleic acids]

Question 1

What are the advantages of scientists questioning the validity of a current theory rather than automatically accepting it

Answer 1

Alternative theories can be explored and investigated.
As a result new facts may emerge and so a new theory is put forward or the existing one is modified

Question 2

Justifiy why it is necessary for society to analyse the risk and benefits of these discoveries befire they are developed

Answer 2

Society will probably be affected by new discoveries and so is entitled to say how they can or cannot be used

Question 3

Prime location

Answer 3

5’ carbon is attached to the phosphate group
3’ prime end is attached to the hydroxyl group

Question 4

Prime location

Answer 4

When nucleotides are organised into the oduble strands of a DNA moleucle, one strand runs in the 5’ to 3’ direction whilst the other runs in the 3’ to 5’ end–>The two strands are said to be antiparallel

Question 5

Why can DNA polymerase only synthesise nucleic acids ‘in vivo’ (5’ to 3’ direction)

Answer 5

The DNA Polymerase that assembles the nucleotides into a DNA molecule can only attach nucleotides to the hydroxyl group on the 3’ end

Question 6

Explain why DNA Polymerase can only attach to the nucleotides to the hydroxyl group on the 3’ carbon molecule

Answer 6

Enzymes are very specific.
They have active sites that are of a specifc shape that fits their substrate
The shape of the 3’ end of the molecule with its hydroxyl group fits the active site of DNA polymerase