Question 18N.3.SL.TZ0.1d
| Date | November 2018 | Marks available | [Maximum mark: 1] | Reference code | 18N.3.SL.TZ0.1d |
| Level | SL | Paper | 3 | Time zone | TZ0 |
| Command term | Suggest | Question number | d | Adapted from | N/A |
A variegated Pelargonium plant was grown outdoors in a plant pot. Figure 1 shows one leaf of the Pelargonium. The plant was left in the dark for 24 hours to inhibit photosynthesis. After this time, a sketch was made of the leaf to show the colours (Figure 2), then part of the leaf was covered with black card (Figure 3). Following the exposure of the plant to sunlight for six hours, the black card was removed and the leaf tested for starch (Figure 4).
Suggest reasons that plants with variegated leaves are rarely found growing wild naturally.
[1]
«having the leaf partly white would be» no selective advantage/cannot compete
OR
natural selection would reduce the frequency of the mutation causing variegated leaves
OR
occur due to artificial selection ✔
Some reference to evolution or natural selection required
Do not accept reference to photosynthesis alone
