Question

( vacuole must top 3) P Chromatophordis famous because the two chromatophores are derived from cyanobacteria which are still present on earth. While all other protists have cyanobacterial endosymbiots that are billions of years old, ancestral arachaeplastids, because P chromatophorais' endosymbiot is unique it suggests A) endosymbiosis in this clade happened more than once B) many different bacteria could give rise to plastids C) that it is possible other endosymbiotic events will be discovered D) all of the above

Answer 1

Answer :

Plastids are organelles that function to capture light energy and enable an organism to carry out the process of photosynthesis. It is accepted that plants and other photosynthetic organisms aquired plastid via endosymbiosis and the associated bacterial cell was a specific type of cyanobacteria in all the case.

However, P. chromatophora has two chromatophores and are derived from a different type of cyanobacteria. Also, the event of endosymbiosis in P. chromatophora took place much recently than others.

This can be possible if endosymbiosis took twice, and involved different types of bacteria. It can be expected that more endosymbiotic events would be discovered in future.

Hence, the correct choice should be:

(D) All of the above.