Question

in chemiosmosis in mitochondria, protons flow from the intermembrane space into the matrix. in what direction do protons flow during chemiosmosis in chloroplasts?

from the stroma into the cytosol

from the matrix into the stroma

from the stroma into the thylakoid space

from the intermembrane space into the stroma

from the thylakoid space to into the stroma

Explanation:

During chemiosmosis in chloroplasts, protons flow down their electrochemical gradient. The thylakoid membrane has a higher proton concentration in the thylakoid space (due to processes like water - splitting and electron transport chain activities). Protons move through ATP synthase (a proton - channel enzyme) from the thylakoid space to the stroma to generate ATP, similar to how protons move from the intermembrane space to the matrix in mitochondria (but in different organelles with different compartments).

Answer:

from the thylakoid space to into the stroma