investigating respiration

• how do we investigate carbon dioxide production before set up?

  • soak dried beans in water for day or two - will germinate - germinating beans will respire
  • boil similar sized second bunch of dried beans - will kill beans - no respiration
• how do we investigate carbon dioxide production while setting up?

  • put same amount of hydrogen-carbonate indicator into two test tubes
  • place platform made of gauze into each test tube and place beans on this.
  • seal test tube with rubber bung
  • leave apparatus for set period of time
  • during time - CO2 produced by germinating beans should have had an effect on hydrogen-carbonate indicator - turned yellow
• how do we investigate temperature change produced by respiration?

  • add each set of beans to vacuum flask - ensure some air left in flasks for beans to aerobically respire
  • place thermometer into each flask and seal top with cotton wool
  • record temperature of each flask daily for a week
  • repeat using same mass of beans every time
  • beans well insulated in flask - when germinating beans respire - test flask's temperature will increase compared to control flask (dead beans)