Question 18M.3.HL.TZ1.12
| Date | May 2018 | Marks available | [Maximum mark: 5] | Reference code | 18M.3.HL.TZ1.12 |
| Level | HL | Paper | 3 | Time zone | TZ1 |
| Command term | Describe, Outline | Question number | 12 | Adapted from | N/A |
Caenorhabditis elegans, a nematode, was the first multicellular organism whose genome was completely sequenced.
Outline the benefits of using model organisms for studying gene function.
[2]
a. organisms with similar gene sequence could be used as models for specific gene functions (in humans)
b. it is possible for researchers to learn about the gene function faster/more easily as fewer genes (in model)
c. can predict effects in other organisms
d. some research may be unethical in humans
Describe how BLAST can be used to establish phylogenetic relationships between several organisms.
[3]
a. results from BLASTn or BLASTp /genomic or proteomic sequences can be used
b. compared with data from available organisms
c. matches based on the number of similarities in the sequence are identified
d. similarities in sequence may be caused by evolution or by chance
e. computer programs (use sequence alignments) to suggest evolutionary relationships / cladograms can be constructed
