The existence of common features in different forms of life indicates some relationship between the different organisms, and according to the concept of evolution, these relations stem from the circumstance that the higher organisms, in the course of millions of years, have gradually evolved from simpler ones.

In the course of the 1920s and 1930s, great progress was made in the study of the intermediary reactions by which sugar is anaerobically fermented to lactic acid or to ethanol and carbon dioxide.

Hans Adolf Krebs Quotes