Difference Between RBC and Hemoglobin (With Table)

RBC is also known as Red blood corpuscles or erythrocytes. They are the common type of blood cell in vertebrates. Their main function is to supply oxygen to all the body cells. The oxygen molecules entering the lungs through respiration are taken up by the RBCs and are transported to different parts of the body through circulation.

Hemoglobin is a protein in the red blood cells. It helps the RBC in carrying oxygen and carbon dioxide. Hemoglobin is a metalloprotein. It has Iron and globin. It gives RBC and blood its red color. Hemoglobin is a red-colored pigment. There are many other pigments like hemoglobin that are present in some invertebrates.

Comparison Table Between RBC and Hemoglobin

What is RBC?

Red blood corpuscles are enucleated, oval, or biconcave disk-shaped structures. They are formed and matured in the bone marrow. Their lifespan is 100-120 days. They lack a nucleus as they make space to accommodate the red pigment hemoglobin. 2.4 million new RBCs are produced every second in humans. They make up 40-45% of the total volume of blood.

The cell membrane of RBC is permeable for oxygen molecules. Oxygen enters RBC through diffusion. It then travels in the blood to different body parts and enters the cells. Human RBC has a diameter of 6.2-8.2µm. Women have 4-5 million RBC per microliter of blood while, men have 5-6 million RBC per microliter of blood.

Their major function is to transport oxygen. During stressful conditions, RBCs release ATP which leads to the relaxation of blood vessels which eventually leads to normal blood flow. They also have some immunological functions. When attacked by a pathogen they release free radicals to lyse the cell wall of the pathogen and kill it.

Having a normal RBC count is healthy. An increase or decrease in the number of RBC may cause certain diseases. A decrease in the number of RBC leads to a condition called Anemia. Anemia may be caused by Vitamin B12 or folate deficiency, stomach ulcer, or excessive blood loss. An increase in the number of RBC causes Polycythemia.

What is Hemoglobin?

Hemoglobin is the protein pigment present in RBC. It is made up of four amino acid chains. A heme group is attached to each of these chains. The heme group is made up of a porphyrin ring and an iron atom. Each hemoglobin molecule can carry four oxygen atoms.

The iron atoms temporarily bind with the oxygen atoms. This binding is temporary and on reaching the target cells oxygen dissociates and enters the cells. Hemoglobin also carries back a small amount of carbon dioxide which is the waste product of cellular respiration.

Hemoglobin also causes changes in blood color. When hemoglobin combines with oxygen forming Oxyhemoglobin, the blood is scarlet or bright red. When the oxygen is released deoxyhemoglobin is formed which gives the blood a dark burgundy color. Hemoglobin also combines with carbon monoxide forming carboxyhemoglobin. Hemoglobin is responsible for the transportation of 98% of the total oxygen in humans.

The hemoglobin content of a healthy individual is 12-14 g per 100ml of blood. Hemoglobin makes up 96% of the total weight of RBC. Hemoglobin is also present in other body parts like macrophages, alveolar cells, lungs, hepatocytes, retinal pigment, etc and functions as an antioxidant and iron metabolism regulator.

Main Differences Between RBC and Hemoglobin

1. RBCs are blood cells involved in oxygen transportation. Whereas, hemoglobin is the pigment present in RBC which binds with oxygen and is responsible for oxygen transportation by RBC.
2. RBC is biconcave, disc-shaped, enucleated blood cells produced in the bone marrow. While hemoglobin is a metalloprotein made up of globin and heme.
3. An increase in RBC causes Polycythemia while increase in hemoglobin causes hemoglobinemia.
4. A decrease in RBC causes a condition called anemia characterized by fatigue and pale skin. A decrease in hemoglobin leads to thalassemia, engagement of spleen, vasculitis, and anemia by lowering the RBC’s ability to carry oxygen.
5. The main function of hemoglobin is to bind with respiratory gases and hold them. But, RBC has a major function of transporting the gases bound to hemoglobin to different parts of the body through blood.

Conclusion

Though, RBC and hemoglobin are both components of blood they are different from each other. A decrease in hemoglobin or abnormal hemoglobin can affect the normal functioning of RBC. Anemia is a common problem caused by issues related to RBC and hemoglobin count. Hemoglobin content can be increased by eating food that is rich in Iron and Vit B12. Consuming iron-rich spinach, greens, dates, and red meat can help deal with these diseases.

Besides these deficiency diseases, some genetic diseases like sickle cell anemia can also affect the normal activity of RBC. In sickle cell anemia the RBC are crescent-shaped and they clump together causing a block. These crescent RBCs cannot efficiently transport oxygen.

Taking a healthy diet including eggs, meat, spinach, tofu, beetroot, liver, asparagus, polyester, Apple, green beans, and folate-rich food maintains a normal RBC count, and hemoglobin level and helps to avoid Anemia.

References

1. https://onlinelibrary.wiley.com/doi/abs/10.1002/ajh.25937
2. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1525-1594.2004.07394.x