Basic purpose of this lecture is to present on Living Factories; focus on Yeast. We may not look much like yeast or they like us, but many of the 6,000 genes in yeast have counterparts in humans. Yeast as a Living Organism: As a living organism, just like us, yeast needs the following to survive and flourish: sugars, water, warmth etc. Yeast are single celled microorganism, they are type of fungus and exist on all living matter.