The role of hemoglobin in oxygen transport is crucial for respiration in vertebrates. Hemoglobin, a protein found in red blood cells, binds to oxygen in the lungs and transports it to tissues throughout the body. Each hemoglobin molecule can carry up to four oxygen molecules, enhancing the efficiency of oxygen delivery. Additionally, hemoglobin aids in the transport of carbon dioxide back to the lungs for exhalation, playing a vital role in maintaining blood pH and overall respiratory function.