Endosymbiotic features in organelles

Steps:

• Chloroplasts and mitochondria originated from ancient prokaryotic bacteria via endosymbiosis.
• Prokaryotes contain 70S ribosomes for protein synthesis and circular DNA as their genome.
• These organelles retain prokaryotic traits, unlike the eukaryotic cell's 80S ribosomes and linear DNA.
• Compare options to identify the matching prokaryotic features.

Why B is correct:

• Endosymbiotic theory defines these organelles by prokaryotic inheritance, including 70S ribosomes for translation and circular DNA for independent replication.

Why the others are wrong:

• A: Omits circular DNA, a key prokaryotic feature in both organelles.
• C: 80S ribosomes are eukaryotic cytoplasmic, not found in chloroplasts or mitochondria.
• D: Excludes 70S ribosomes, essential for organelle-specific protein synthesis.

Final answer: B