Higher Tier: controlling plant growth commercially
| English | 中文 | Pinyin |
|---|---|---|
| rooting powder/ˈruːtɪŋ ˈpaʊdə/ | 生根粉 | shēng gēn fěn |
| seed dormancy/siːd ˈdɔːmənsi/ | 种子休眠 | zhǒng zi xiū mián |
What would explain this observation?
- Higher Tier: A grower may want roots on a cutting, controlled fruit ripening or germination at the right time. The useful hormone depends on the intended result.
- Start with a prediction. State the quantities or features you would compare, then decide what evidence could distinguish two explanations.
Build the model
- Auxins are used as weed killers, rooting powders 生根粉 and to promote growth in tissue culture. Ethene is used in the food industry to control fruit ripening during storage and transport. Gibberellins can end seed dormancy 种子休眠, promote flowering and increase fruit size. Match the use to a specific effect rather than calling every product a general fertilizer.
- rooting powder: A product using plant growth hormones to encourage roots on cuttings; seed dormancy: A state in which a viable seed does not germinate until suitable conditions or signals occur.
Which use matches ethene?
A weed-killer application can change plant diversity and affect organisms depending on those plants. Evaluate intended crop benefits alongside non-target effects, biodiversity and the stated treatment conditions. A rooting comparison measures root formation, while a fruit-size comparison needs dimensions or mass; neither is automatically evidence for the other hormone uses.
Match each technical term to its precise meaning.
Use the definitions to distinguish related quantities and processes.
Choose evidence that can test it
- A weed-killer application can change plant diversity and affect organisms depending on those plants. Evaluate intended crop benefits alongside non-target effects, biodiversity and the stated treatment conditions. A rooting comparison measures root formation, while a fruit-size comparison needs dimensions or mass; neither is automatically evidence for the other hormone uses.
- Use fictional horticultural trials or teacher-supervised approved propagation. Keep plant variety, cutting size, growth conditions and observation time comparable. Follow school product handling instructions; do not apply weed killers to a habitat or release ripening gases as an independent school task. Tissue culture requires approved aseptic methods rather than unknown cultures.
Which two habits make the investigation or model in this case more defensible?
Use fictional horticultural trials or teacher-supervised approved propagation. Keep plant variety, cutting size, growth conditions and observation time comparable. Follow school product handling instructions; do not apply weed killers to a habitat or release ripening gases as an independent school task. Tissue culture requires approved aseptic methods rather than unknown cultures.
Work from known quantities
- State the known values and their units. Choose the relation because its assumptions fit this case, then rearrange before substitution.
- Known: a fictional rooting trial has 18 rooted cuttings among 24 with a stated treatment and 12 among 24 in a control. Proportions are 75% and 50%; difference = 25 percentage points. This supports the stated rooting comparison, not an unlimited dose response or a recommendation for every plant.
A fictional trial has 21 rooted cuttings among 28. Calculate the percentage. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
A fictional trial has 21 rooted cuttings among 28. Calculate the percentage.
The result is 75 %. Known: a fictional rooting trial has 18 rooted cuttings among 24 with a stated treatment and 12 among 24 in a control. Proportions are 75% and 50%; difference = 25 percentage points. This supports the stated rooting comparison, not an unlimited dose response or a recommendation for every plant.
Check the conclusion and its limits
- Hormones coordinate growth; mineral fertilizers provide nutrients and are a different intervention. A result for cuttings does not prove a fruit-ripening effect. Commercial benefits do not remove the need to evaluate non-target and biodiversity effects.
- Return to the original observation. Explain what the result supports, which conditions it assumes, and one way to test a competing explanation.
A growth hormone is the same intervention as a mineral fertilizer. This claim is false: Hormones coordinate growth; mineral fertilizers provide nutrients and are a different intervention. A result for cuttings does not prove a fruit-ripening effect. Commercial benefits do not remove the need to evaluate non-target and biodiversity effects.
Higher Tier: controlling plant growth commercially: A weed-killer application can change plant diversity and affect organisms depending on those plants. Evaluate intended crop benefits alongside non-target effects, biodiversity and the stated treatment conditions. A rooting comparison measures root formation, while a fruit-size comparison needs dimensions or mass; neither is automatically evidence for the other hormone uses.
A growth hormone is the same intervention as a mineral fertilizer.
Hormones coordinate growth; mineral fertilizers provide nutrients and are a different intervention. A result for cuttings does not prove a fruit-ripening effect. Commercial benefits do not remove the need to evaluate non-target and biodiversity effects.
A product using plant growth hormones to encourage roots on cuttings: write the technical term.
rooting powder means A product using plant growth hormones to encourage roots on cuttings.