The endosymbiotic theory provides an explanation for the evolution of chloroplasts and mitochondria within eukaryotic cells.
This hypothesis posits that eukaryotes developed through a mechanism in which different types of free-living prokaryotes were absorbed into larger prokaryotic cells, eventually transforming into chloroplasts, mitochondria, and other organelles.
The digestive activity is regulated by mechanical and chemical receptors found in the walls of the tract organs.
