(a)[3]
Proteins have several ‘levels’ of bonding: primary, secondary and tertiary. Complete the table to show which level of bonding is responsible for these features: formation of $\alpha$-helix; formation of disulfide bonds; formation of ionic bonds; linking amino acids.
(b)[4]
The diagram shows part of a DNA molecule. Examine the diagram and state the correct names for the blocks labelled J, K, L and M.
(c(i))[1]
What type of bonding keeps the DNA polymer strands together?
(c(ii))[1]
Explain why this kind of bonding enables the base pairs within the strands to separate during replication at normal body temperature.
(d)[1]
In RNA polymer, two of the blocks, J, K, L or M, have different identities. For one block that is different, give its correct name in DNA and in RNA.