Skill:
• Analysis of results from experiments involving measurement of respiration rates in germinating seeds or
invertebrates using a respirometer
A respirometer is a device that determines an organism’s respiration rate by measuring the rate of exchange of O2 and CO2
- The living specimen (e.g. germinating seeds or invertebrate organism) is enclosed in a sealed container
- Carbon dioxide production can be measured with a data logger or by pH changes if the specimen is immersed in water
- When an alkali is included to absorb CO2, oxygen consumption can be measured as a change in pressure within the system
- The pressure change can be detected with a data logger or via use of a U-tube manometer
Factors which may affect respiration rates include temperature, hydration, light (plants), age and activity levels
- An increase in carbon dioxide levels will indicate an increase in respiration (CO2 is a product of aerobic respiration)
- A decrease in oxygen levels will indicate an increase in respiration (O2 is a requirement for aerobic respiration)
Schematic of a Simple Respirometer Designed to Measure Oxygen Uptake
