Describe the importance of the inner membranes separating different regions of the mitochondrion and the chloroplast.

The inner membrane of these two organelles serves as the  site of   accommodating protons  to generate   the electrochemical gradients needed to supply energy for ATPase synthase and therefore ATPs synthesis.

These membrane are impermeable, unlike the outer membranes of the these organelles. Therefore  protons leakages is prevented which ensures continuous  build up  of electrochemical gradients for ATPase synthase.

Theses membranes also  increases the surface area of these organelles to increases the amount of protons accommodated.

Finally  the membranes contains some proteins needed for electron transport chain,which ensures continuous PMF for proton gradient.

Explanation:

layer 3 is younger than layer 6.