Find the word definition

Wiktionary
quantasome

n. Any of an array of particles, on the inner surface of a chloroplast, in which photosynthesis takes place

Wikipedia
Quantasome

Quantasomes are particles found in the thylakoid membrane of chloroplasts. in which photosynthesis takes place.This particle that is embedded in a paracrystalline array on the surface of thylakoid discs in chloroplasts. Quantasomes are composed equally of lipids and proteins, which include various photosynthetic pigments and redox carriers. For this reason they are considered to be photosynthetic units. They occur in 2 sizes: the smaller quantasome is thought to represent the site of photosystem I, the larger to represent the site of photosystem II.

They were first identified by Roderic B. Park in 1962.