Question

which of the following did not provide evidence that chloroplasts arose from the engulfment of a cyanobacterium by a eukaryotic cell? presence of cyanobacterial pigments in red algae presence of cyanobacterial photosynthetic pigments in green plants presence of peptidoglycan in glaucophytes nucleic acid sequencing electron microscopy

Explanation:

The endosymbiotic theory for the origin of chloroplasts suggests they originated from engulfed cyanobacteria. Electron microscopy can show chloroplast - like structures similar to cyanobacteria. Nucleic acid sequencing can reveal genetic similarities between chloroplasts and cyanobacteria. The presence of cyanobacterial photosynthetic pigments in green plants and cyanobacterial pigments in red algae are also evidence. Glaucophytes have peptidoglycan in their chloroplast - like structures (cyanelles), which is a characteristic of cyanobacteria. The presence of peptidoglycan in glaucophytes provides evidence for the endosymbiotic origin of chloroplasts, so it is not the answer for what did not provide evidence.

Answer:

Presence of peptidoglycan in glaucophytes