Key Difference – Iron vs Hemoglobin
Iron and hemoglobin are two essential components in the blood. Hemoglobin is a complex protein molecule in red blood cells that carries oxygen from the lung to the body tissues and returns carbon dioxide from the body tissues to the lung for the removal. Iron is an essential element required for blood production and it’s a constituent of hemoglobin. This is the key difference between Iron and Hemoglobin.
CONTENTS
1. Overview and Key Difference
2. What is Iron
3. What is Hemoglobin
4. Side by Side Comparison – Iron vs Hemoglobin
5. Summary
What is Iron?
Iron is a chemical which plays many roles in the body including, oxygen transportation, carbon dioxide removal, DNA synthesis, generation of ATP via electron transport chain, and production of key enzymes in the body. It is an essential component in the blood synthesis. Oxygen and carbon dioxide transportation through the blood circulation is mainly facilitated by the iron atoms in the hemoglobin of the red bold cells. Majority of the iron in our body is found in hemoglobin and a minority is found in myoglobin and cytochromes.
Dietary irons are absorbed as ferrous ions via duodenum. Absorption of iron from diets depend on several factors. Absorption can be enhanced by the consumption of vitamin C containing foods simultaneously with iron rich foods. Polyphenols, some animal proteins, calcium ions, phytates are known as inhibitors of iron absorption.
Maintaining proper levels of iron in the body is essential. Therefore, iron uptake, transport, storage, and utilization should be well organized and regulated since the deficiency and excess levels can cause several complications in body. Iron should be stored and supplied adequately to cells for their optimum metabolism. Excessive levels of iron can lead to hemochromatosis, fibrosis, cirrhosis etc. Iron deficiency can cause depletion of iron stores in the body, causing a condition called iron deficiency anemia and other cellular dysfunctions. Therefore, homeostasis of iron is very critical in the body.
Iron loss from the body happens due to several reasons. Loosing blood, urination, defecation, sweating, exfoliation of cells from the epithelial surfaces, excessive bleeding during menstruation, bleeding during the pregnancy etc. create iron deficiency in the body. Iron deficiency can be overcome using medication, iron rich foods, iron supplements etc. without permitting the deficiency to convert into iron deficiency anemia condition. It’s a critical condition showing chronic symptoms as shown in figure 01.
Figure 1: Symptoms of anemia
What is Hemoglobin?
Hemoglobin is an iron containing red blood cell protein responsible for transportation of oxygen from the lung to the body tissues and organs, and transportation of carbon dioxide from body tissues to the lung. It is also known as oxygen carrying protein in the blood. It is a complex protein consisting of four small protein subunits and four heme groups bearing iron atoms as shown in figure 02. Hemoglobin has a high affinity for oxygen. There are four oxygen binding sites located inside the hemoglobin molecule. Once hemoglobin saturates with oxygen, the blood become bright red in colour and is known as oxygenated hemoglobin. The second state of the hemoglobin where oxygen is not bound with oxygen is known as deoxyhemoglobin. In this state, blood bears the dark red colour.
It is the iron atom embedded inside the heme compound of hemoglobin that mainly facilitates the oxygen and carbon dioxide transportation. Binding of oxygen molecules to Fe+2 ions changes the conformation of the hemoglobin molecule. Iron atoms in the hemoglobin also helps to maintain the typical shape of the red blood cell. Therefore, iron is a vital element found in the red blood cells.
Figure 2: Structure of Hemoglobin
What is the difference between Iron and Hemoglobin?
Iron vs Hemoglobin |
|
| Iron is an element found in the body. | Hemoglobin is a protein found in the red blood cells. |
| Functions | |
| This is responsible for blood synthesis, ATP generation, DNA synthesis, oxygen transport, carbon dioxide transport, enzyme production etc. | This is mainly responsible for carrying oxygen from the lung to the body tissues and organs, and returning carbon dioxide to the lung. |
| Relationship between iron and hemoglobin | |
| Iron is a constituent of hemoglobin which is responsible for the main function of the hemoglobin | Hemoglobin molecule contains four atoms of iron. Iron atoms are responsible for the structure and activity of the hemoglobin. |
Summary – Iron vs Hemoglobin
Hemoglobin is an iron containing metalloprotein found in red blood cells. It carries oxygen from lungs to the body tissues and facilitates the energy production. It also returns carbon dioxide from the body tissues to the lung. Iron is an element vital for blood production and action of hemoglobin in red blood cells. It is also responsible for the colour and the shape of the red blood cells. This is the difference between iron and hemoglobin.
Reference:
1. Abbaspour, Nazanin, Richard Hurrell, and Roya Kelishadi. “Review on iron and its importance for human health.” Journal of Research in Medical Sciences: The Official Journal of Isfahan University of Medical Sciences. Medknow Publications & Media Pvt Ltd, Feb. 2014. Web. 20 Feb. 2017.
2. National Academy of Sciences (US) and National Research Council (US) Division of Medical Sciences. “THE ROLE OF IRON IN HEMOGLOBIN SYNTHESIS.” Conference on Hemoglobin: 2–3 May 1957. U.S. National Library of Medicine, 01 Jan. 1970. Web. 20 Feb. 2017
3. Schechter, Alan N. “Hemoglobin research and the origins of molecular medicine.” Blood. American Society of Hematology, 15 Nov. 2008. Web. 20 Feb. 2017
Image Courtesy:
1. “Symptoms of anemia” -Häggström, Mikael. “Medical gallery of Mikael Häggström 2014”. WikiJournal of Medicine DOI:10.15347/wjm/2014.008. ISSN 20018762. (Public Domain) via Commons Wikimedia
2. “1904 Hemoglobin”By OpenStax College – Anatomy & Physiology, Connexions Web site. (CC BY 3.0) via Commons Wikimedia
