OCR A 5.1.5 · 20 written questions · 48 marks · about 60 minutes · marked as you go
This free quiz has 20 written exam questions on plant and animal responses, all taken from OCR A Level Biology A papers (A level, 2018 to 2025). Short answers mark themselves. For longer answers you write your answer, then tick off the OCR mark-scheme points you made, so you see exactly where the marks are. Twenty real OCR A Level exam questions on plant and animal responses, from tropisms and plant hormones to the nervous system, the control of heart rate and muscle contraction.
What the quiz covers (OCR A spec 5.1.5)
Plant responses (5.1.5(a)(i)–(ii)): naming tropisms, responses to abiotic stress, chemical defences against herbivores, and how seedling tropism experiments are set up.
Plant hormones (5.1.5(b)): how hormones control seed germination, and which hormone affects root growth.
Experimental evidence (5.1.5(c)–(e)): interpreting data on auxin and apical dominance, and the effect of inhibiting gibberellin on stem length.
Commercial uses of plant hormones (5.1.5(f)): evaluating advice on using ethene to ripen fruit.
Nervous system, brain and reflexes (5.1.5(g)–(i)): the peripheral and autonomic systems, the brain region that controls heart rate, spinal reflexes and the blink reflex.
Coordination and heart rate (5.1.5(j)–(k)): adrenaline, adenylyl cyclase and cAMP, and correcting errors in an account of heart rate control.
Muscle (5.1.5(l)(i)–(ii)): skeletal, cardiac and involuntary muscle, electron micrographs of sarcomeres, rigor mortis and the neuromuscular junction.
How to use it
Write every answer in full, as you would in the exam: the mark for each question is shown, so you know how much to write. When you self-mark, only tick a point if your answer clearly makes it, then read the examiner's tip under each question. Your progress is saved on your device, so you can do it in two sittings, and at the end you can retry just the questions where you dropped marks.
Prefer multiple choice? Try the 15-question Plant and Animal Responses multiple choice quiz first.
Open the Plant and Animal Responses quiz in a new tab (easier on a phone)
Where students lose marks (from OCR examiners' reports and mark schemes)
Each point below is followed by wording that gained marks.
Read the log scale the right way: On a graph with a logarithmic concentration axis, some students think 10⁻⁹ is a higher concentration than 10⁻³, so every conclusion comes out backwards.
✔ Gains credit: The more negative the power, the lower the concentration: at the highest auxin concentrations, lateral shoot growth is inhibited.
Say which shoot, and at what concentration: Conclusions about auxin data lose marks when they don't say whether the effect is on apical or lateral shoots, or don't refer to high/low concentrations or quote data.
✔ Gains credit: Low auxin concentrations stimulate lateral shoot growth, but high concentrations inhibit it while stimulating the apical shoot.
Ethene is a gas: Few students spotted that spraying a fruit tree outdoors with ethene is unlikely to work.
✔ Gains credit: Ethene is a gas, so outdoors it would diffuse away; ripening with ethene normally needs closed, controlled conditions.
Ethene also makes fruit drop: Students stop at 'ethene ripens fruit' in a 3-mark evaluation.
✔ Gains credit: Ethene also promotes fruit abscission, so the apples might fall and be damaged; the dose and stage of ripeness matter too.
Inhibiting production lowers the concentration: Very few students said what a chemical that inhibits gibberellin production actually does to the plant.
✔ Gains credit: The chemical reduces the gibberellin concentration, so the stems are shorter and the plants stay upright.
Explain why the yield goes up: Students just repeat that yield increases, which the question already says.
✔ Gains credit: Plants that don't fall over are less damaged, so more can be harvested, and less resource goes into stem growth.
Carbonic acid, not carbon dioxide: When correcting an account of heart rate control, many replaced 'carboxylic acid' with carbon dioxide, which OCR ignored.
✔ Gains credit: Carboxylic acid should be carbonic acid (H₂CO₃).
The nerve goes to the SAN: Students write 'the SAN sends an impulse to the AVN' instead of correcting where the nerve impulses arrive.
✔ Gains credit: The accelerator (sympathetic) nerve sends impulses to the SAN, not the AVN.
Keep practising
Try the Plant and Animal Responses multiple choice quiz, the Neuronal and Hormonal Communication multiple choice quiz, the Hormonal Communication written quiz or the Photosynthesis written quiz, or browse all our OCR A Level Biology quizzes. Our OCR A masterclasses (Year 12 on Wednesdays at 5.15pm, Year 13 on Tuesdays at 6.30pm) work through real exam questions on one topic each week.
Questions, mark schemes and examiners' report extracts © OCR.