R. H. Whittaker, On the Broad Classification of Organisms, The Quarterly Review of Biology, Vol. 34, No. 3 (Sep., 1959), pp. 210-226 ...

Organisms reproducing via asexuality harbor a great diversity of lineages, morphotypes and ecotypes. However, classification of asexual taxa does not fit into contemporary species concepts, and hence ...

Most reactions in living organisms involve the "electrons" transfer, which is called redox reaction. For example, respiration and photosynthesis can be classified as redox reactions.