Major objective of this lecture is to present on Living Factories; here major focus on Yeast as a Living Organism. As a living organism, just like us, yeast needs the following to survive and flourish: sugars, water and warmth. This lecture also present on Aerobic Respiration; in aerobic respiration glucose reacts with oxygen in the mitochondria of the cells to release energy. Finally present on Fermentation. Living yeast cells in the absence of oxygen are still able to use sugar as their source of food to make energy.