Final answer:
The diffusion of hydrogen ions through the mitochondrial membrane without the need for integral membrane proteins would lead to decreased ATP production, as the electrochemical gradient necessary for ATP synthase to operate would dissipate.
Step-by-step explanation:
If hydrogen ions were able to diffuse through the mitochondrial membrane into the mitochondria without the need for integral membrane proteins, the outcome would be decreased ATP production. This is because ATP synthesis in the mitochondria is dependent on the electrochemical gradient of hydrogen ions across the inner mitochondrial membrane. Under normal circumstances, hydrogen ions accumulate in the intermembrane space, creating a high concentration of hydrogen ions compared to the mitochondrial matrix. This gradient is critical for ATP synthase to function, as the flow of hydrogen ions through ATP synthase powers the conversion of ADP to ATP, a process known as chemiosmosis.
If the membrane were permeable to hydrogen ions, this gradient would dissipate as ions would simply diffuse back into the matrix, thus removing the driving force necessary for ATP synthase to work. Consequently, this would lead to decreased ATP production as the hydrogen ions would no longer be forced through ATP synthase.