CAIE A-Level Biology A2 15.2.1 Venus Fly Trap Rapid Response Questions
Explain the rapid response of the Venus fly trap using evidence from each question and mark scheme.
- Syllabus
- 2028–2030
- Course
- Biology 9700
- Level
- A2
Exam points
- Explain the rapid response of the Venus fly trap.
CAIE A-Level Biology A2 15.2.1 Venus Fly Trap Rapid Response Questions question 1
[Maximum number: 5]
The Venus fly trap, Dionaea muscipula, is a carnivorous plant. It has traps which catch insects.
Each trap consists of a pair of modified leaves joined by a midrib of hinge cells. The modified leaves have touch-sensitive hairs. If two hairs are touched within 20 seconds, or the same hair is touched twice in rapid succession, the trap closes.
Explain how touching the hairs results in closure of the trap.
any five from:
1. (touching hairs causes), action potential / depolarisation ;
2. auxin increase triggered in hinge cells ;
3. H+/ hydrogen ions, pumped into cell walls ;
4. calcium pectate 'glue' in cell wall dissolved ;
5. Ca2+ ions enter hinge cell ;
6. water follows by osmosis ;
7. hinge / midrib, cells expand ;
8. trap lobes, flip from convex to concave / change in elastic tension ;
All question bank results loaded