When ancestral photosynthetic euglenids obtained their chloroplasts, the result was a chloroplast surrounded by three membranes.This is evidence of acquisition of the chloroplast by
A) primary endosymbiosis.
B) secondary endosymbiosis, retaining the chloroplast from a green alga.
C) secondary endosymbiosis, retaining the chloroplast from a plant.
D) tertiary endosymbiosis.
E) quaternary endosymbiosis.

Question

Quizplus · Accepted Answer

The presence of three membranes around the chloroplast is indicative of secondary endosymbiosis, where a eukaryotic cell engulfs another eukaryotic cell that already contains a chloroplast. In the case of photosynthetic euglenids, the chloroplasts were acquired through the engulfment of a green alga.

When Ancestral Photosynthetic Euglenids Obtained Their Chloroplasts, the Result Was