Giardia is eukaryotic yet is long thought to lack a mitochondira. Recently, researchers have found that each Giardia cell contains double membrane-bound organelles similar to a mitochondria called mitosomes that lack mtDNA. What is the best explanation for mitosomes?
◦ Mitosomes are the ancestral form of the mitochondria.
◦ Mitochondria in Giardia evolved into mitosomes and have lost or transferred their DNA to the Giardia nuclear genome.
◦ Mitosomes evolved from another Giardia organelle that lacked DNA.
◦ Mitosomes are more advantageous to eukaryotes than mitochondria.
◦ Giardia are asexual and thus do not require mitochondria with its own DNA.