What happens to the free energy released as electrons are passed from photosystem ii to photosystem i through a series of electron carriers? it is used to establish and maintain a proton gradient. it is used to phosphorylate nad+ to nadph. it excites electrons of the reaction center in photosystem i. it is used to synthesize atp through substrate-level phosphorylation?

primary succession occurs in essentially lifeless areas regions in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier. secondary succession occurs

bradykinin is a physiologically and pharmacologically active peptide of the kinin group of proteins, consisting of nine amino acids.