Endosümbiootiline

Endosümbiootiline refers to a symbiotic relationship where one organism lives inside another. This living arrangement is not external but internal, with the symbiont residing within the host's cells or tissues. A classic and highly significant example of endosymbiosis is the origin of eukaryotic organelles such as mitochondria and chloroplasts. According to the endosymbiotic theory, these organelles were once free-living prokaryotic organisms that were engulfed by an ancestral host cell. Instead of being digested, they established a mutually beneficial relationship, leading to their integration into the host and eventually their evolution into essential components of eukaryotic life. Mitochondria, responsible for cellular respiration, are thought to have originated from aerobic bacteria, while chloroplasts, the sites of photosynthesis, are believed to have originated from cyanobacteria. This process of endosymbiosis has been crucial in the diversification of life on Earth, enabling the development of complex cellular structures and metabolic capabilities. The term can also describe other instances where one microbe lives within another, providing benefits such as nutrient acquisition or protection.