Thylakoids possess photosynthetic units called

Thylakoids possess photosynthetic units called Quantasomes.
Quantasomes are particles found in the thylakoid membrane of chloroplasts in which photosynthesis takes place. They are embedded in a paracrystalline array on the surface of thylakoid discs in chloroplasts. They are composed of lipids and proteins that include various photosynthetic pigments and redox carriers.
Quantasomes were first identified by Roderic B. Park in 1962. Each quantasome contains about 230 - 250 chlorophyll molecules and 50 molecules of carotenoids.