Define the terms chromosome, gene, allele and genome.

Compare the genetic material of prokaryotes and eukaryotes.

Explain the process of DNA replication.

chromosome: structure formed by DNA and proteins;
gene: a heritable factor that controls a specific characteristic;
allele: one specific form of a gene occupying the same gene locus as other alleles of the gene;
genome: the whole of the genetic information of an organism;

Responses do not need to be shown in a table format.

occurs during (S phase of) interphase/in preparation for mitosis/cell division;
DNA replication is semi-conservative;
unwinding of double helix/separation of strands by helicase;
hydrogen bonds between two strands are broken;
each strand of parent DNA used as template;
deoxynucleoside triphosphate provides energy;
synthesis continuous on leading strand but not continuous on lagging strand;
resulting in formation of Okazaki fragments (on lagging strand);
synthesis occurs in 5'→3' direction;
RNA primer synthesized on parent DNA using RNA primase;
DNA polymerase III adds the nucleotides (to the 3' end);
complementary base pairing;
adenine pairs with thymine and cytosine pairs with guanine; (both pairings required) (do not accept letters alone)
DNA polymerase I removes the RNA primers and replaces them with DNA;
DNA ligase joins Okazaki fragments/seals nicks (in sugar-phosphate backbone);
Accept any of the above points shown in a clearly annotated diagram.

This was the most popular question by far. It also tended to be the best answered. Most candidates were attempting to describe chromosome, gene, allele and genome, rather than defining as asked. The definitions in the syllabus were expected or very close alternatives.  

Better-prepared candidates scored well on part b, being able to competently compare the genetic material in prokaryotes and eukaryotes. Weak answers were caused by missing the word "genetic material‟ and just compared the two, scoring very few marks. A large number inappropriately defined naked DNA as being DNA that is not enclosed within a nucleus rather than DNA that is not associated with histones.

The explanation of DNA replication was well known by all but the least well prepared candidates. Many gave answers of textbook quality. It should be mentioned that if diagrams are included they should be clear and well labelled.