Compare three respiration equations
| English | 中文 | Pinyin |
|---|---|---|
| aerobic respiration/eəˈrəʊbɪk ˌrespɪˈreɪʃn/ | 有氧呼吸 | yǒu yǎng hū xī |
| fermentation/fɜːmənˈteɪʃn/ | 发酵 | fā jiào |
What would explain this observation?
- Muscle cells and yeast can both transfer energy without oxygen, but their products differ. Name the organism before selecting the anaerobic equation.
- Start with a prediction. State the quantities or features you would compare, then decide what evidence could distinguish two explanations.
Build the model
- Cellular respiration is continuously occurring in living cells and is exothermic. It transfers energy needed for chemical reactions building larger molecules, movement and keeping warm. Aerobic respiration 有氧呼吸 uses oxygen: glucose + oxygen → carbon dioxide + water. Required symbols are C₆H₁₂O₆, O₂, CO₂ and H₂O.
- aerobic respiration: Cellular respiration using oxygen; fermentation 发酵: Anaerobic respiration in yeast producing ethanol and carbon dioxide.
Which products match anaerobic respiration in yeast?
Anaerobic respiration in muscle is glucose → lactic acid. Oxidation is incomplete, so much less energy is transferred than in aerobic respiration. In plant and yeast cells, anaerobic respiration is glucose → ethanol + carbon dioxide. Yeast fermentation is economically useful: carbon dioxide helps bread dough rise, and ethanol is used in alcoholic-drink manufacture.
Match each technical term to its precise meaning.
Use the definitions to distinguish related quantities and processes.
Choose evidence that can test it
- Anaerobic respiration in muscle is glucose → lactic acid. Oxidation is incomplete, so much less energy is transferred than in aerobic respiration. In plant and yeast cells, anaerobic respiration is glucose → ethanol + carbon dioxide. Yeast fermentation is economically useful: carbon dioxide helps bread dough rise, and ethanol is used in alcoholic-drink manufacture.
- Build a comparison table with oxygen requirement, products and relative energy transfer. Use teacher-provided fermentation data or a supervised approved yeast practical; control temperature, substrate amount and observation time. Keep apparatus safely vented according to school instructions. Do not infer an energy yield from gas volume alone or introduce unrequired ATP counts.
Which two habits make the investigation or model in this case more defensible?
Build a comparison table with oxygen requirement, products and relative energy transfer. Use teacher-provided fermentation data or a supervised approved yeast practical; control temperature, substrate amount and observation time. Keep apparatus safely vented according to school instructions. Do not infer an energy yield from gas volume alone or introduce unrequired ATP counts.
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: an approved yeast model produces 18 cm³ gas in 6 minutes, giving a mean rate of 3 cm³ per minute. A matched condition produces 12 cm³ in the same time, or 2 cm³ per minute. This compares carbon dioxide output under the stated conditions; it is not a direct comparison of muscle lactic-acid production.
An approved yeast model produces 20 cm³ gas in 5 minutes. Calculate mean output rate. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
An approved yeast model produces 20 cm³ gas in 5 minutes. Calculate mean output rate.
The result is 4 cm³/min. Known: an approved yeast model produces 18 cm³ gas in 6 minutes, giving a mean rate of 3 cm³ per minute. A matched condition produces 12 cm³ in the same time, or 2 cm³ per minute. This compares carbon dioxide output under the stated conditions; it is not a direct comparison of muscle lactic-acid production.
Check the conclusion and its limits
- Respiration is a chemical process in cells, whereas breathing moves air. Plants also respire. Carbon dioxide is a product of the yeast anaerobic model but is not a product of the muscle equation here. Less energy transfer is not the same as no energy transfer.
- Return to the original observation. Explain what the result supports, which conditions it assumes, and one way to test a competing explanation.
Anaerobic respiration in muscles produces ethanol and carbon dioxide. This claim is false: Respiration is a chemical process in cells, whereas breathing moves air. Plants also respire. Carbon dioxide is a product of the yeast anaerobic model but is not a product of the muscle equation here. Less energy transfer is not the same as no energy transfer.
Compare three respiration equations: Anaerobic respiration in muscle is glucose → lactic acid. Oxidation is incomplete, so much less energy is transferred than in aerobic respiration. In plant and yeast cells, anaerobic respiration is glucose → ethanol + carbon dioxide. Yeast fermentation is economically useful: carbon dioxide helps bread dough rise, and ethanol is used in alcoholic-drink manufacture.
Anaerobic respiration in muscles produces ethanol and carbon dioxide.
Respiration is a chemical process in cells, whereas breathing moves air. Plants also respire. Carbon dioxide is a product of the yeast anaerobic model but is not a product of the muscle equation here. Less energy transfer is not the same as no energy transfer.
Cellular respiration using oxygen: write the technical term.
aerobic respiration means Cellular respiration using oxygen.