Practical - Repsirometer

Question 1

What are the Apparatus used to measure the rate of respiration with a respirometer

Answer 1

• Respirometer
• Glass beads
• Germinating seeds (respiring organism)
• Test tubes
• Soda-lime pellets (absorb CO2)
• stopwatch

Question 2

How to calculate the volume of oxygen taken in using a respirometer

Answer 2

• internal area of the tube x distance moved by liquid
• πr2h

Question 3

What are the Limitations of the respirometer practical

Answer 3

• cannot be used to measure the rate of anaerobic respiration, as no oxygen is consumed

Question 4

What is the method used to measure the rate of respiration using a repspirometer

Answer 4

1. set up the apparatus and use the distance moved by the liquid in the manometer to calculate the change in volume
2. allow air to reenter via the screw cap and reset the fluid using the syringe
3. make a change to the dependent variable you’re measuring, allow it to acclimatise
4. close screw clip and restart experiment

Question 5

What happens if there is no soda lime in the repsirometer

Answer 5

• The same volume of CO2 and O2 will be produced
• no movement of the manometer liquid

Question 6

What way will the liquid move with soda lime in the test tube

Answer 6

• CO2 doesn’t affect the volume of gas
• oxygen is consumed
• liquid moves towards the experimental tube