What is the role of plastocyanin in the z-scheme model? see section 10.3 (page 219) . view available hint(s) what is the role of plastocyanin in the z-scheme model? see section 10.3 (page 219) . it captures the photon energy that excites electrons. it shuttles electrons between the cytochrome complex and photosystem i. it transfers electrons directly from photosystem ii to photosystem i. it carries protons across the thylakoid membrane to produce a proton gradient used in atp synthesis. submit?