Question

For the phospholipid bilayer of the inner membrane of mitochondria, which layer is the cytosolic face?

A. The layer facing matrix
B. The layer facing intermembrane space

Answer 1

The cytosolic face of the inner mitochondrial membrane is the layer facing the intermembrane space. The correct option is B.

Step-by-step explanation:

For the phospholipid bilayer of the inner membrane of mitochondria, the cytosolic face is the layer that faces the intermembrane space. This inner membrane contains folds called cristae, which increase its surface area, and it is where ATP synthesis takes place.

The inner membrane encases the mitochondrial matrix, which is where processes such as the Krebs cycle occur. It is important to understand that in mitochondria, the intermembrane space is the area between the inner and outer membranes.

Since the outer membrane separates the mitochondrion from the cytosol, the inner membrane's section facing the intermembrane space is considered the cytosolic face. Option B. is the correct one.