Dialysis Technician Practice Exam

What is the oxygen-carrying red pigment found in red blood cells?

1. Hemoglobin

2. Myoglobin

3. Chlorophyll

4. Fibrinogen

The correct answer is: Hemoglobin

The oxygen-carrying red pigment found in red blood cells is hemoglobin. Hemoglobin is a complex protein that binds to oxygen molecules in the lungs and transports them throughout the body to tissues and organs that require oxygen for metabolism and energy production. Its structure allows it to efficiently pick up oxygen where it is abundant and release it in areas where oxygen levels are lower. Myoglobin, while also an oxygen-binding protein, is found primarily in muscle tissue and serves a different function—it facilitates the storage of oxygen for use during muscle contraction, rather than transporting oxygen throughout the body like hemoglobin does. Chlorophyll is a pigment found in plants that is crucial for photosynthesis, allowing plants to absorb energy from light, but it is not involved in carrying oxygen in blood. Fibrinogen is a protein involved in the blood clotting process, converting into fibrin to help form clots during injury, and does not have any role in oxygen transportation. Understanding the specific roles of these different proteins and pigments is vital in the context of human physiology and the functions of the circulatory and muscular systems.