We can consider cellular energy conversions—like all other energy conversions—in the context of the laws of thermodynamics. - Albert L. Lehninger

The remarkable similarity of metabolic pathways and gene sequences across the phyla argues strongly that all modern organisms are derived from a common evolutionary progenitor by a series of small changes (mutations), each of which conferred a selective advantage to some organism in some ecological niche.

All living organisms fall into one of three large groups (domains) [Bacteria, Archeara, Eukarya] that define three branches of evolution from a common progenitor.

Virtually every chemical reaction in a cell occurs at a significant rate only because of the presence of enzymes.