Question 20N.3.SL.TZ0.10c
| Date | November 2020 | Marks available | [Maximum mark: 2] | Reference code | 20N.3.SL.TZ0.10c |
| Level | SL | Paper | 3 | Time zone | TZ0 |
| Command term | Describe | Question number | c | Adapted from | N/A |
Aequorea victoria is a jellyfish that produces green fluorescent protein (GFP) which glows in blue light. The gene for GFP has been isolated and can be used as a marker gene. Plants with the gene incorporated glow when exposed to blue light.
[Source: [jellyfish image] Sierra Blakely, Attribution, via Wikimedia Commons.]
[leaves (middle image)] El-Shemy HA, Khalafalla MM, Ishimoto M. The role of green fluorescent protein (GFP)
in transgenic plants to reduce gene silencing phenomena. Curr Issues Mol Biol. 2009;11 Suppl 1:i21–28.
Epub 2009 Feb 2. PMID: 19193961.
[seedlings (right image)] Clark, David & Kim, Joo Young & Cho, Keun Ho & Colquhoun, Thomas. (2019). Strong
Fluorescence Expression of ZsGreen1 in Petunia Flowers by Agrobacterium tumefaciens–mediated Transformation.
Journal of the American Society for Horticultural Science. American Society for Horticultural Science. 144. 405–413.
10.21273/JASHS04776-19. https://journals.ashs.org/jashs/view/journals/jashs/144/6/article-p405.xml.
Describe how an open reading frame (ORF) can be identified.
[2]
a. can be identified with bioinformatics software / example of software;
b. locate a sequence corresponding to a start codon/ATG (sense strand);
c. read this sequence until a stop codon/TGA/TAG /TAA is reached;
