respirometers and respiratory substrates

What about a substrate determines how effectively it can be respired

The number of hydrogens

What is the RQ value for glucose/carbohydrates

1

What is the RQ value for Lipids

0.7

What is the RQ value for Proteins

0.9

How can an RQ value be calculated

• from a balanced chemical equation

• (Moles of CO2 given out)/(moles of O2 taken in)

What does a really high number RQ value above 1 mean about the respiration occuring

High proportion of anaerobic respiration occuring

What are the advantages of using this respirometer

• simple to submerge in water bath to change temperature

• Syringe resets respirometer easily

• Scale easy to read

• Movement of manometer scale should give volume of O2 taken up

What is the purpose of potassium hydroxide solution

Absorbs any CO2 produced so that only the oxygen is affecting the change in gas volume

Explain this respirometer

• the movement of liquid = volume of O2 produced

• Soda lime added absorbs CO2 - gas shouldnt move as far as less gas produced

What are the limitations of this respirometer

• no reset

• No fixed scale

• No control tube - need separate equipment

How would you find the volume of gas from a capillary tube from a respirometer

• area of tube x length

• πr² x distance moved

How would you find the RQ value experimental using a respirometer set up

• measure volume of O2 consumed (with KOH)(VOL1)

• Reset respiometer

• Rerun experiment with no KOH (VOL2)

• RQ = [(O2 consumed)-(O2consumed-CO2 produced)] / O2 consumed

• RQ = [VOL1-VOL2]/VOL1