Which of the following is a true statement about hemoglobin?

Hemoglobin is a crucial protein found in red blood cells that plays a key role in transporting oxygen from the lungs to the tissues of the body. Its structure allows it to bind with oxygen molecules efficiently, facilitating this vital process. This function is essential for maintaining cellular respiration and overall metabolic health, making oxygen transport its primary and most significant role.

While white blood cells are involved in the immune response, they do not contain hemoglobin. Hemoglobin is also not involved in regulating blood sugar levels, which is primarily the function of insulin and other hormones. Additionally, hemoglobin is not muscle tissue; it is a protein found within red blood cells, distinct from the muscle fibers that comprise muscle tissue. Therefore, the statement about hemoglobin helping in oxygen transport is accurate and reflects its fundamental biological importance.