IB Biology HL 3.4.8 Desert Plant Adaptations Question Bank
Practise IB Biology HL 3.4.8 by explaining how desert plants reduce transpiration and collect or store scarce water.
- Syllabus
- First assessment 2025
- Course
- Biology HL
- Level
- HL
Practise IB Biology HL 3.4.8 by explaining how desert plants reduce transpiration and collect or store scarce water.
The photo shows vegetation in the Sonoran Desert, which is part of the hot desert biome.

Explain three adaptations of plants that can help them survive in the dry conditions of hot deserts.
a. extensive roots (to collect water from a wide area/to collect water after rainfall);
b. deep roots to collect water from underground sources;
c. (thick) waxy cuticle to reduce transpiration/water loss/evaporation;
d. water storage tissue/thick stems/thick leaves/succulent (to survive droughts);
e. no leaves/narrow leaves/rolled leaves/spines instead of leaves to reduce the surface area for transpiration/evaporation;
f. fewer stomata/sunken/pitted stomata to reduce transpiration/water loss;
g. vertical stems to reduce exposure to sun at midday/heating when the sun is overhead/hottest OR
pleated stems to allow shrinkage and reswelling/to store water;
h. stomata open at night/CAM metabolism;
Mark first three adaptations
only.
3
Marking guidance:
max