Question 18N.3.HL.TZ0.11e
| Date | November 2018 | Marks available | [Maximum mark: 2] | Reference code | 18N.3.HL.TZ0.11e |
| Level | HL | Paper | 3 | Time zone | TZ0 |
| Command term | Outline | Question number | e | Adapted from | N/A |
Golden rice (Oryza sativa, GR) is the generic name given to genetically modified rice that produces beta-carotene (provitamin A). Golden rice was created by transforming rice with the gene coding for the PSY protein (phytoene synthase) from daffodil (Narcissus pseudonarcissus) or from corn (Zea mays).
The picture shows variations of rice.
A White wild-type rice
B Yellow Golden rice expressing the gene coding for PSY from daffodil
C Orange Golden rice expressing the gene coding for PSY from corn
[Reprinted from TRENDS in Plant Science, 10(12), S. Al-Babili and P. Beyer, 'Golden Rice – five years on the road – five years to go?',
pp. 565--573, Copyright (2005), with permission from Elsevier. https://www.sciencedirect.com/journal/trends-in-plant-science]
BLASTp was used to obtain the alignment of the genes coding for PSY. Outline reasons for BLASTn not being suitable for obtaining this alignment.
[2]
a. BLASTp aligns amino acids «of proteins» ✔
b. BLASTn aligns nucleotides «of DNA/RNA» ✔
c. amino acid sequence is shown therefore BLASTn would not work ✔
