So if the cell contains oxygen and it commits to cellular respiration, these two pyruvate molecules are then transported into the mitochondrial matrix of the mitochondrion inside that cell. So let's say this is the cytoplasm of the cell. This is the mitochondrion, which contains the outer membrane, the inner membrane. We have the intermembrane space and we have the mitochondrial space. Now, if our cell commits to cellular respiration in the presence of oxygen, these two pyruvates are transported via specialized proteins known as integral proteins. So we have integral proteins on the outer membrane and integral proteins on the inner membrane, shown in green.