| Criteria | Marks |
|---|
| • Explains the role of RNA polymerase in reproduction of the rabies virus, including reference to transcription, production of proteins and viral RNA replication<br>• Relates newly produced proteins to RNA polymerase and viral RNA replication | 5 |
| • Describes the role of RNA polymerase in reproduction of the rabies virus, including reference to transcription, production of proteins and viral RNA replication<br>• Relates newly produced proteins to RNA polymerase | 4 |
| • Outlines the role of RNA polymerase in reproduction of the rabies virus including reference to the processes of transcription and RNA replication | 3 |
| • Provides some features of the role of RNA polymerase in reproduction of the rabies virus | 2 |
| • Provides some relevant information | 1 |
Sample answer:
The viral RNA polymerase, which is made up of the L and P proteins, is responsible for the production of viral proteins and viral RNA, which are the components of new rabies viral particles. RNA polymerase is responsible for transcription of the viral RNA into complementary mRNA strands, which are then translated into rabies viral proteins, G, M, N, P and L, by host cell ribosomes. The replication of rabies viral RNA is facilitated by the newly produced L and P proteins (RNA polymerase). In this process, a complementary strand of viral RNA is produced from the original viral RNA strand. This complementary strand is then used as a template for the RNA polymerase to catalyse the production of more viral RNA. The new strands produced are therefore the same as the original viral RNA. RNA polymerase is responsible for both the viral RNA and proteins needed in reproducing the virus.
