What is the origin of chloroplasts?

Answer 1

Mitochondria and chloroplasts likely evolved from engulfed prokaryotes that once lived as independent organisms. At some point, a eukaryotic cell engulfed an aerobic prokaryote, which then formed an endosymbiotic relationship with the host eukaryote, gradually developing into a mitochondrion. Eukaryotic cells containing mitochondria then engulfed photosynthetic prokaryotes, which evolved to become specialized chloroplast organelles.

Answer 2

Chloroplasts originated from a process called endosymbiosis, where a eukaryotic cell engulfed a photosynthetic cyanobacteria. Over time, a symbiotic relationship developed where the cyanobacteria became integrated into the cell and evolved into what we now recognize as chloroplasts. This event is believed to have occurred around 1.5 billion years ago, contributing to the evolution of photosynthetic organisms.

Answer 3

Chloroplasts appear to have originated from a photosynthetic prokaryote that lived inside a eukaryotic cell.