Final answer:
Hemoglobin is the protein responsible for transporting oxygen from the lungs to the tissues of the body, and it also helps to carry carbon dioxide back to the lungs. It contains iron in its heme groups which binds to oxygen, making it an essential component of the red blood cells.
Step-by-step explanation:
The protein that transports oxygen from the lungs to other parts of the body is hemoglobin. Hemoglobin is found within red blood cells and consists of four protein subunits: two alpha and two beta. Each subunit surrounds an iron-containing heme group which binds oxygen molecules. The iron in heme gives hemoglobin its ability to bind oxygen and is responsible for the red color of blood.
As oxygen diffuses from the alveolar air space in the lungs into the bloodstream, it binds to the iron present in the heme groups of hemoglobin, forming oxyhemoglobin. This binding increases as more oxygen molecules are bound, allowing efficient transportation of oxygen to the body's tissues. Upon reaching tissues, oxygen is released from hemoglobin, which then binds to carbon dioxide for transport back to the lungs.
Hemoglobin not only carries oxygen but also helps in the transport of carbon dioxide from tissues back to the lungs. Diseases and altered bodily conditions can affect hemoglobin's oxygen-binding ability, which is crucial for maintaining proper oxygen levels throughout the body's tissues.