Answer to Question #179025 in Biology for Lia

Question

What evolutionary advantages did endosymbiosis bring to the development of biological diversity, in your opinion?

( it has to be 200 words to 400)

Answer 1

The emergence of endosymbiosis was associated with the formation of two-membrane organelles possessing a certain level of autonomous work in a cell. The formation of mitochondria and plastids (i.e., chloroplasts) in cells significantly improved energetic homeostasis contributing to the formation and development of new biochemical pathways for the synthesis of large amounts of ATP. The formation of chloroplasts resulted in the evolution of autotrophic organisms (plants and algae) that are able to synthesize organic compounds from carbon dioxide and water using solar energy. As a result, these organisms could inhabit new ecological niches and now are widely distributed in marine and water ecosystems, as well as on lands. The initial introduction of chloroplasts and intensive growth of phytoplankton (uni- and multicellular algae) resulted in extensive production of oxygen as a byproduct of photosynthesis occurring in chloroplasts. Now, organisms could use oxygen as a terminal electron acceptor increasing their metabolic rate and improving their survival rate. The emergence of mitochondria improved ATP synthesis by introducing oxidative phosphorylation to cells. Mitochondria could successfully use oxygen for a high metabolic rate. Similar to chloroplasts, organisms with mitochondria now could inhabit new niches and adapt to various environments increasing biodiversity.