Answer:
the proton gradient will decrease
Explanation:
The proton concentration gradient is generated across the inner mitochondrial membrane. It is maintained since the inner mitochondrial membrane is impermeable for protons. Therefore, intermembrane space has a higher concentration of proton than the matrix. The opening of UCP1 that facilitates the diffusion of protons would dissipate the proton concentration gradient as protons will move back to the matrix through the opened channels. The proton concentration will be lost as heat.