ATI Pathophysiology Practice Exam

What is the iron-containing component of red blood cells?

1. Albumin

2. Myoglobin

3. Hemoglobin

4. Transferrin

The correct answer is: Hemoglobin

The iron-containing component of red blood cells is hemoglobin. Hemoglobin is a protein that binds oxygen in the lungs and transports it to the tissues throughout the body. Its structure includes heme groups, which contain iron, allowing it to effectively carry oxygen. When oxygen binds to the iron in hemoglobin, it undergoes a conformational change that facilitates the release of oxygen in areas where it is needed, such as muscles and organs. Other components listed have specific functions but do not serve as the primary oxygen transport molecule in red blood cells. For instance, albumin is a protein found in blood plasma that helps maintain oncotic pressure and transport substances but does not contain iron. Myoglobin, found in muscle tissue, also binds oxygen but is different from hemoglobin and serves to store oxygen rather than transport it in the blood. Transferrin is a plasma protein that binds iron and is responsible for its transport in the bloodstream, but it does not reside within red blood cells. Thus, hemoglobin is uniquely essential for oxygen transport due to its iron content.