Practical - Investigate factors affecting the respiration of yeast
Respiration that occurs in the absence of oxygen. can be demonstrated by removing oxygen from yeast鈥檚 surroundings.
Procedure
- Boil the glucose solution to sterilise it and remove any oxygen, leaving behind the glucose needed for anaerobic respiration.
- Cool before adding the yeast (high temperatures will kill it).
- Place a layer of oil on top of the glucose solution to prevent oxygen entering.
- Yeast will respire anaerobically producing alcohol, heat and carbon dioxide that can be collected in A chemical that changes from colourless to cloudy/milky when carbon dioxide is added..