What is the role of hemoglobin molecules?

What is the role of hemoglobin molecules?

• A. To transport nutrients
• B. To scavenge for foreign material
• C. To transport respiratory gases
• D. To help maintain the shape of red blood cells

Answer: (C)

Hemoglobin’s job is to transport respiratory gases. It is a protein in red blood cells with iron-containing heme groups that bind oxygen in the lungs and release it to tissues, supporting cellular respiration. As tissues produce carbon dioxide, it is picked up by hemoglobin (forming carbaminohemoglobin) and carried back to the lungs to be exhaled; most CO2 is also carried as bicarbonate in plasma. Hemoglobin also helps buffer blood pH as oxygenation changes. Other functions aren’t its main role: nutrients are carried by different plasma components and transport systems, scavenging of foreign material is done by immune components, and the shape of red blood cells is maintained mainly by the cell membrane and cytoskeleton, not by hemoglobin.

Hemoglobin’s job is to transport respiratory gases. It is a protein in red blood cells with iron-containing heme groups that bind oxygen in the lungs and release it to tissues, supporting cellular respiration. As tissues produce carbon dioxide, it is picked up by hemoglobin (forming carbaminohemoglobin) and carried back to the lungs to be exhaled; most CO2 is also carried as bicarbonate in plasma. Hemoglobin also helps buffer blood pH as oxygenation changes.

Other functions aren’t its main role: nutrients are carried by different plasma components and transport systems, scavenging of foreign material is done by immune components, and the shape of red blood cells is maintained mainly by the cell membrane and cytoskeleton, not by hemoglobin.