Question 19M.2.SL.TZ2.4
| Date | May 2019 | Marks available | [Maximum mark: 8] | Reference code | 19M.2.SL.TZ2.4 |
| Level | SL | Paper | 2 | Time zone | TZ2 |
| Command term | Deduce, Explain, Outline, State | Question number | 4 | Adapted from | N/A |
The images show parts of plants belonging to two different phyla.
State the phylum of plant X and of plant Y.
X:
Y:
[2]
X: Filicinophyta ✔
Y: Coniferophyta/Conifera/Gymnosperms ✔
Those who had been taught it could identify the filicinophyte and the coniferophyte, albeit with a variety of spellings.
Explain one cause of mutation.
[2]
Not chromosomal.
Many were confused by a relatively simple question, but a large proportion gained both marks by linking radiation or carcinogens to changes in the DNA base sequence.
Outline the types of evidence that can be used to place a species in a particular clade.
[3]
a. a clade is a group of organisms that have evolved from a common ancestor ✔
b. identify the base sequences of a gene ✔
c. identify amino acid sequence of a protein ✔
d. comparing homologous structures ✔
e. the fewer the differences, the closer they diverged in time from a common ancestor ✔ Accept vice versa.
Those who had been taught it gained at least two marks for evidence and clades, with comparing base sequences of genes and amino acid sequences of proteins amongst the most common correct answers.
The cladogram includes four marsupial (non-placental mammal) families.
[Source: Koala image: Quartl, https://commons.wikimedia.org/wiki/Phascolarctos_cinereus#/media/
File:Friendly_Female_Koala.JPG; Wombat image: JJ Harrison, https://en.wikipedia.org/wiki/Wombat#/
media/File:Vombatus_ursinus_-Maria_Island_National_Park.jpg; Marsupial lion: Nobu Tamura,
https://en.wikipedia.org/wiki/Marsupial_lion#/media/File:Thylacoleo_BW.jpg;
Diprotodontoidea image: Anne Musser]
Deduce the family that is most closely related to the Diprotodontoidea.
[1]
Vombatidae/wombats ✔
Nearly everyone spotted the wombat correctly.