How do you show germinating seeds release heat?
Reveal answer
Vacuum flask with germinating seeds and thermometer; control with boiled, disinfected seeds; record temperature over days.
Key words: vacuum flask · boiled
2(f) RESPIRATION · RECALL
2.39 Carbon dioxide and heat from respiring organisms
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How do you show small animals release CO₂?
Reveal answer
Woodlice on gauze over hydrogencarbonate indicator in a sealed tube; control with glass beads; indicator red → yellow.
Key words: hydrogencarbonate · yellow
Hydrogencarbonate indicator colours.
Reveal answer
Purple: low CO₂. Red: air level. Yellow: high CO₂.
Key words: purple · red · yellow
Brief CORMMSS for temperature and maggot respiration.
Reveal answer
C: 5 water-bath temperatures; O: same-size maggots; R: ×3 mean; M1: liquid distance in respirometer; M2: after 10 min; S1: same mass of maggots; S2: same soda lime.
Key words: respirometer · soda lime
What does soda lime do in a respirometer?
Reveal answer
Absorbs carbon dioxide, so liquid movement shows oxygen uptake.
Key words: carbon dioxide · oxygen
What is meant by the term hydrogen-carbonate indicator?
Reveal answer
An indicator that changes colour with carbon-dioxide concentration through associated pH change.
Key words: hydrogen-carbonate indicator
What is meant by the term germinating seed?
Reveal answer
A seed in active early growth with a relatively high respiration rate.
Key words: germinating seed
What is meant by the term non-respiring control?
Reveal answer
A matched control experiment lacking living respiration.
Key words: non-respiring control
What is meant by the term insulation?
Reveal answer
Material or design that reduces heat transfer to the surroundings.
Key words: insulation
What is meant by the term semi-quantitative?
Reveal answer
Providing ordered or approximate differences rather than exact concentrations.
Key words: semi-quantitative
Two linked respiration investigations, CO₂ indicator. Expected living result? Matched control experiment and interpretation?
Reveal answer
Expected living result: Red/orange moves toward yellow. Matched control experiment and interpretation: Glass beads remain near reference colour; living material raised CO₂.
Key words: CO₂ indicator
Two linked respiration investigations, Insulated-flask temperature. Expected living result? Matched control experiment and interpretation?
Reveal answer
Expected living result: Temperature rises above starting value. Matched control experiment and interpretation: Non-respiring control experiment changes less; living respiration released heat.
Key words: Insulated-flask temperature
Two linked respiration investigations, Replicates. Expected living result? Matched control experiment and interpretation?
Reveal answer
Expected living result: Similar direction across trials. Matched control experiment and interpretation: Spread shows random variation.
Key words: Replicates
Two linked respiration investigations, Sensor improvement. Expected living result? Matched control experiment and interpretation?
Reveal answer
Expected living result: Continuous CO₂ or temperature data. Matched control experiment and interpretation: More objective and higher-resolution evidence.
Key words: Sensor improvement
True or false, and why? “Yellow indicator proves oxygen was produced.”
Reveal answer
False. It supports increased carbon dioxide concentration.
True or false, and why? “Boiled seeds are automatically a perfect control experiment.”
Reveal answer
False. Microbial contamination or unequal volume and water content can confound the comparison.
True or false, and why? “The vacuum flask must be completely airtight.”
Reveal answer
False. Respiring seeds need gas exchange; a cotton-wool plug limits heat loss while admitting air.
True or false, and why? “No temperature rise means seeds did not respire.”
Reveal answer
False. Heat loss or low respiration rate may make a rise too small to detect.