What do we call the organism that does photosynthesis but does not release oxygen?

Among the following, which compound does not play an important role in photosynthesis?

When CO2: O2 is approximately 1, RuBisCO has a lower affinity for CO2. True or false?

CO2 assimilation during photosynthesis is of 3 types. True or false?

_____ is the only product in cyclic photophosphorylation.

PS I is the photosystem present only in ___ photosynthesis.

Joseph Priestley did his experiments with which organism?

What were the isotopes used, to research about photosynthesis?