Which term describes the role of hemoglobin?

Which term describes the role of hemoglobin?

• A. Lymph capillaries
• B. Pulmonary circulation
• C. Oxygen transport protein
• D. Hemoglobin

Answer: (D)

The main idea here is what hemoglobin does in the blood. Hemoglobin’s job is to act as an oxygen transport protein. It binds oxygen in the lungs (via the iron in its heme groups), carries it through the bloodstream, and releases it to tissues that need it. It also helps move some carbon dioxide from tissues back to the lungs to be exhaled. Lymph capillaries are part of the lymphatic system, not related to oxygen transport. Pulmonary circulation describes the path blood takes to the lungs, not the function of hemoglobin itself. Describing hemoglobin simply as the molecule doesn’t capture its role. So the best description of its role is that it is an oxygen transport protein.

The main idea here is what hemoglobin does in the blood. Hemoglobin’s job is to act as an oxygen transport protein. It binds oxygen in the lungs (via the iron in its heme groups), carries it through the bloodstream, and releases it to tissues that need it. It also helps move some carbon dioxide from tissues back to the lungs to be exhaled. Lymph capillaries are part of the lymphatic system, not related to oxygen transport. Pulmonary circulation describes the path blood takes to the lungs, not the function of hemoglobin itself. Describing hemoglobin simply as the molecule doesn’t capture its role. So the best description of its role is that it is an oxygen transport protein.