| Date | May 2019 | Marks available | 1 | Reference code | 19M.3.HL.TZ2.12 |
| Level | Higher level | Paper | Paper 3 | Time zone | Time zone 2 |
| Command term | State | Question number | 12 | Adapted from | N/A |
Question
Biopharming is the use of genetically modified plants or animals as a source of pharmaceutical products.
Outline how a named vector is used to introduce a new gene into a plant.
State the role of marker genes.
Markscheme
ALTERNATIVE 1
a. Agrobacterium tumefaciens contains a tumour-inducing/Ti plasmid ✔
b. required/target gene inserted into plasmid ✔
c. bacterium injects modified plasmid into plant cell and DNA becomes incorporated into plant cell nucleus ✔
ALTERNATIVE 2
d. tobacco mosaic virus/TMV is the vector ✔
e. required/target gene inserted into TMV ✔
f. TMV injects modified DNA into plant cell «and DNA becomes incorporated into plant cell nucleus» ✔
to verify that the target gene has been incorporated in the target cell/organism ✔
OWTTE
Examiners report
Most had some knowledge about the usage of vectors to introduce genes, but their difficulty was in structuring their answer.
Most could state the role of marker genes.
