Why is it advantage to have hemoglobin in the blood?

Hemoglobin is advantageous because it efficiently transports oxygen from the lungs to tissues throughout the body, facilitating cellular respiration and energy production. Additionally, it helps carry carbon dioxide, a waste product, from tissues back to the lungs for exhalation. This dual function is crucial for maintaining proper metabolic processes and overall homeostasis. Furthermore, hemoglobin's ability to bind oxygen reversibly allows for flexible oxygen delivery based on the body's varying demands.