Glucose --> Ethanol + Carbon Dioxide + Energy
Used to make Beer
Glucose + Oxygen --> Carbon Dioxide + Water + Energy
Used to make bread
Yeast converts sugars to carbon dioxide and some ethanol.
The carbon dioxide is what makes the bread rise.
As the carbon dioxide expands, it gets trapped in the dough, making it lighter.
The dough is kneaded, trapping air which provides a source of oxygen for Aerobic respiration.
Conditions For Bread Making
Temperature - Enzymes like to work in warm conditions (about 35°C)
Glucose - needed for respiration
Aerobic Conditions - Maximises CO2 produced
pH - Doesn't really matter