Lesson 5.1.5a

5.1.5a Plant responses and plant hormones Quiz: OCR Biology, Unit 5

20 questions

In partnership with Revision Ninja

Lesson 5.1.5a, Plant responses and plant hormones: 20 multiple choice questions for the OCR Biology (H020), Unit 5: Communication and homeostasis, written with Revision Ninja.

Host it live on the board and students join with a game code on their own devices, or revise alone with Free Play. The answers are revealed in the game.

Host this setFree Play

The 20 questions

  1. Which term describes a directional growth response of a plant to light?

    • Phototropism
    • Geotropism
    • Thigmonasty
    • Chemotaxis
  2. Which tropism describes the downward growth of roots in response to gravity?

    • Chemotropism towards sugars
    • Positive thigmotropism
    • Negative phototropism
    • Positive geotropism
  3. Which plant hormone is primarily responsible for maintaining apical dominance?

    • Auxin
    • Gibberellin
    • Ethene
    • Abscisic acid
  4. How does auxin produced in the apical bud affect lateral buds?

    • Promotes division
    • Triggers abscission
    • Stimulates elongation
    • Inhibits growth
  5. Which plant hormone promotes stem elongation and breaks seed dormancy to trigger germination?

    • Ethene
    • Abscisic acid
    • Gibberellin
    • Cytokinin
  6. Which plant hormone triggers stomatal closure during water stress?

    • Auxin
    • Abscisic acid
    • Gibberellin
    • Ethene
  7. What experimental procedure demonstrates that the apical bud inhibits lateral bud growth?

    • Covering stem base
    • Removing shoot tip
    • Shading lower leaves
    • Watering root system
  8. Where does auxin accumulate when a plant shoot is exposed to unilateral light?

    • Root tip
    • Vascular bundle
    • Shaded side
    • Illuminated side
  9. What is the main effect of applying synthetic auxin rooting powder to stem cuttings?

    • Stimulates root growth
    • Prevents leaf drop
    • Inhibits cell division
    • Accelerates fruit ripening
  10. Why do synthetic auxin weedkillers selectively target broadleaved weeds instead of narrow-leaved grasses?

    • Higher auxin sensitivity
    • Absence of stomata
    • Faster photosynthesis rate
    • Thicker leaf cuticle
  11. What effect does applying gibberellin to dormant seeds typically have?

    • Prevents amylase production
    • Stimulates seed germination
    • Inhibits root growth
    • Induces stomatal closure
  12. Which gas is commercially applied to green fruit to promote uniform ripening?

    • Carbon dioxide
    • Oxygen
    • Ethene
    • Methane
  13. What is the main purpose of performing a serial dilution of a plant hormone?

    • Increase hormone purity
    • Produce known concentrations
    • Prevent chemical breakdown
    • Maintain constant pH
  14. Which variable must be controlled when investigating the effect of gibberellin on stem elongation?

    • Temperature
    • Final stem height
    • Gibberellin concentration
    • Stem length change
  15. Which plant process is directly inhibited by high concentrations of auxin in the apical bud?

    • Leaf abscission
    • Root cell division
    • Lateral bud growth
    • Stem elongation
  16. What is the purpose of a control placed in uniform light during phototropism experiments?

    • Maximise photosynthesis rate
    • Inhibit stem growth
    • Confirm directional response
    • Destroy plant auxins
  17. Which compounds are described in the specification as chemical defences against herbivory?

    • Chlorophyll and carotenoids
    • Insulin and glucagon
    • Alkaloids and pheromones
    • Starch and cellulose
  18. What type of rapid response is shown when a Mimosa pudica leaf folds upon touch?

    • Thigmotropism
    • Geotropism
    • Nastic response
    • Phototropism
  19. Which plant hormone primarily stimulates stem elongation and seed germination?

    • Abscisic acid
    • Auxin
    • Gibberellin
    • Ethene
  20. Which plant hormone accumulates in sealed packaging to accelerate fruit ripening?

    • Auxin
    • Cytokinin
    • Ethene
    • Gibberellin

All OCR Biology quizzes