The lactose permease transporter of E. coli can accumulate lactose inside the cell by transporting lactose in against a concentration gradient, driven by a co-transport process in which the same protein brings protons into the cell from a higher concentration outside to a lower concentration inside.

A. What is the term used to describe the process (a type of active transport) in which one solute is transported against its concentration gradient by co-transport with another solute moving in the favorable direction? _______ active transport

B. If the proton gradient provided a driving force of –10 kJ/mol to support a maximum ?Gt of +10 kJ/mol for the lactose gradient, what would be the maximum lactose gradient (ratio of lactoseinside/lactoseoutside) that the cell could accumulate? Show your calculation.