16 exam-style questions. Write your answer, check it against the mark scheme and tick the points you earned. Your marks stay on this device. Your writing is not saved.
Ratings are saved in this browser on this device, under a KS4 key kept separate from International A Level recall. Written answers are temporary and cleared when you leave the page. Use Reset to clear the ratings on this device.
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
Explain how auxin causes a shoot to bend towards light.
(4)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 4 marks
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
Where is auxin made in a shoot?
(1)Total for this question: 1 mark
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
The tip of an oat shoot is removed and the shoot is lit from one side. Predict what happens and explain.
(2)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 2 marks
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
The tip is cut off, placed on an agar block for an hour, then the block is put on the cut shoot in the dark. Predict and explain the result.
(2)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 2 marks
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
An agar block with auxin is placed on one side of a cut shoot in the dark. Predict and explain the result.
(2)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 2 marks
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
A mica sheet is pushed into the shaded side of a shoot just below the tip. Explain why the shoot does not bend towards the light.
(2)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 2 marks
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
Illustrative data.
| Auxin / arbitrary units | Increase in length / mm |
|---|---|
| 0 | 2 |
| 1 | 6 |
| 2 | 11 |
| 4 | 15 |
| 8 | 9 |
| 16 | 3 |
Describe the effect of auxin concentration on stem growth.
(3)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 3 marks
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
| Auxin / arbitrary units | Increase in length / mm |
|---|---|
| 0 | 2 |
| 1 | 6 |
| 2 | 11 |
| 4 | 15 |
| 8 | 9 |
| 16 | 3 |
Calculate the percentage increase in growth from 0 to 4 units of auxin.
(2)Total for this question: 2 marks
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
| Auxin / arbitrary units | Increase in length / mm |
|---|---|
| 0 | 2 |
| 1 | 6 |
| 2 | 11 |
| 4 | 15 |
| 8 | 9 |
| 16 | 3 |
Suggest why the stem still grows a little with no auxin added.
(2)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 2 marks
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
State the effect of auxin on cells in a shoot.
(1)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 1 mark
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
Explain why light from all sides makes a shoot grow straight up.
(2)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 2 marks
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
Compare the effect of auxin in shoots and in roots.
(2)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 2 marks
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
Gardeners dip cuttings in rooting powder containing auxin. Explain why.
(2)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 2 marks
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
Suggest why some weedkillers contain synthetic auxins.
(2)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 2 marks
3.35 Auxin and phototropism in stems
Exam question
Mark points shown after marking
A student says the experiment with mica sheets proves that auxin moves to the shaded side. Evaluate this statement.
(2)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 2 marks
