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Microbes · Chapter 6: Useful microbes

Year 11 SCX · About 18 minutes with activities · Turn your sound on

Chapter 6 · Useful microbes
CO₂ bubblesmake the dough rise
Alcohol evaporatesin the oven heat
CO₂ holeslight, airy bread

Chapter 6 recap

  • Fermentation: microorganisms convert sugars into products such as ethanol and carbon dioxide, typically without oxygen. Yeast: bread, beer, wine. Bacteria: cheese, yoghurt.
  • Gut microbiome: essential for DAMAGE (digestion, gut–brain axis, metabolic regulation, against pathogens, guardian of immunity, essential nutrients). Dysbiosis: harmful bacteria may outnumber beneficial ones.
  • Decomposers (some bacteria and fungi) break down dead matter. Microbes treat sewage (aerobic tank, anaerobic digester) and drive the nitrogen and carbon cycles.
  • Next: Chapter 7 · Investigating yeast (AS 92020)

Yeast makes alcohol in dough. So why isn’t bread alcoholic?

Chapter 6 · About 18 minutes · sound on

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