Biochemical scientist description

write a description of Federich Woehler, Martin Kamen, Cornelis Bernardus van Niel, the three scientists who contributed to our understanding of gems, germs, and through them respiration , and  photosynthesis by gems. Who were they, When were they and what did they reveal about germs on our planet and perhaps elsewhere.

And why it maybe the gem that is most similar to being a germ when viewed from its physical and chemical properties( take Opals for example).