Question

what is protein pump protein gradient??

Answer 1

It is proton pump and proton gradient.
A proton pump is an integral membrane protein capable of moving protons across the membrane of a cell, mitochondrion, chloroplast or other subcellular compartment.
Proton gradient means the difference in concentration of protons across the inner side of thylakoid membrane and matrix. This proton gradient is responsible for synthesis of ATP during light reaction of photosynthesis.