Biochemical Evidence of Evolution — Overview & Examples

A metabolic process known as fermentation is used to create ATP. Unicellular organisms like yeasts use fermentation, which is often taken advantage of to make products like beer and bread. Multicellular organisms, including humans, also undergo fermentation. When you run and feel like you can't catch your breath and your muscles start to burn, that is because fermentation, which does not use oxygen, is generating ATP and painful lactic acid. What can you conclude about fermentation based on how common it is?