Which of the following best supports the endosymbiont theory that present-day eukaryotic cells are descendants of a successful symbiotic relationship between a host cell and an engulfed prokaryote?

Question

anonymous · Answer

the mitochondria and i think with a single bacteria or just a mere cell.  accordingly the mitochondria itself is a single living organism that is not part of cell organelles but theres a cell that engulf the mitochodria, and it became one of the organelles of that cell. thats what i knnow

anonymous · Answer

The fact that the mitochondrion has it's own genome is a clue to it being a separate organism in the past.