Question

which of the following organisms have only one photosystem?

o chloroplasts
o anoxygenic bacteria
o most algae
o most plants

Explanation:

Chloroplasts in plants and algae, as well as most plants and most algae, have two photosystems (photosystem I and photosystem II) for oxygen - evolving photosynthesis. Anoxygenic bacteria perform photosynthesis without evolving oxygen and have only one photosystem.

Answer:

B. Anoxygenic bacteria