Following are two characteristics of mitochondria and chloroplast that are similar to prokaryotic cells:
Unlike other organelles, both chloroplasts and mitochondria have their own characteristic circular DNA
Both mitochondria and chloroplasts possess their own ribosomes that have 50S and 30S sub-units like a prokaryote instead of 40 and 60S ribosomes found in eukaryotes.
Explanation:
Endosymbiotic Theory:
The endosymbiotic theory helps explain the origins of multi-cellular organisms. An endosymbiont is defined as an organism that lives inside another organism in a state of "endosynmbiosis." The theory states that some of cellular organelles were originally separate prokaryotic organisms engulfed by an amoeba like organism. These engulfed prokaryotes sustained inside the amoeba and evolved into present day mitochondria and chloroplasts.
Mitochondria were formed by engulfing bacteria capable of aerobic respiration.
Chloroplasts were formed when cyanobacteria or photosynthesizing bacteria were engulfed.
Apart from the aforementioned similarities, mitochondria and chloroplasts are roughly the same size as a prokaryotic cell and can self replicate by binary fission.
