The physiological and molecular effects of elevated CO2 levels.

Carbon dioxide (CO2) is an end product of cellular respiration, a process by which organisms including all plants, animals, many fungi and some bacteria obtain energy. CO2 has several physiologic roles in respiration, pH buffering, autoregulation of the blood supply and others. Here we review recent findings from studies in mammalian lung cells, Caenorhabditis elegans and Drosophila melanogaster that help shed light on the molecular sensing and response to hypercapnia.