According to the theory of endosymbiosis, early eukaryotes evolved by symbiotic association of prokaryotes. which two protists evolved from a symbiotic relationship of organisms, which resulted in eukaryotic organisms containing chloroplasts?

Euglena, algae are the two examples contain chloroplast

The protist which evolved from the endo-symbiotic relationship are Euglena and green algae.

Endosymbiosis is the phenomenon of engulfing one organism which can live in symbiotic relationship within.it has deeply impacted the evolution of life.

Green alga were derived by the endosymbiosis with the photosynthetic organism- cyanobacteria as endosymbiosis between a photosynthesizing cyanobacterium and a single-celled protist gave rise to the chloroplast.

Euglena protists are derived from green algae through endosymbiosis as their chloroplasts resemble the chloroplast of algae.

Thus, Euglena and green algae are the protist which resulted from the endosymbiosis.