Myoglobin transfers oxygen obtained from hemoglobin to mitochondrial proteins involved in the catabolism of metabolic fuels to produce energy for the muscle cell. Using what you have learned in this chapter about myoglobin and hemoglobin, what can you conclude about the structures of these mitochondrial proteins?

the calvin cycle takes place in the stroma of the chloroplast. carbon dioxide enters the stroma of the chloroplast to combine with the five-carbon compound called ribulose1, 5-biphosphate to form two molecules of a three-carbon compound called 3-phosphoglyceric acid. this reaction is catalyzed by an enzyme called ribulose bi-phosphate carboxylase.