What is the Difference Between Hemoglobin and Myoglobin?

Hemoglobin and myoglobin are both heme proteins that act as oxygen-binding proteins, but they have distinct differences in their structure and function:

1. Occurrence: Hemoglobin is found in red blood cells and is responsible for transporting oxygen from the lungs to organs throughout the body. Myoglobin, on the other hand, is present in muscle cells and serves as an oxygen storage protein.
2. Structure and Composition: Hemoglobin has a quaternary structure composed of two alpha and two beta subunits, with a molecular weight of 64 kDa. Myoglobin has a tertiary structure and a molecular weight of 16.7 kDa.
3. Function: Hemoglobin's primary function is to transport oxygen from the lungs to the entire body. Myoglobin's main role is to store oxygen for use by muscle tissue.
4. Affinity Towards Oxygen: Hemoglobin has a higher affinity towards oxygen, while myoglobin has a comparatively lower affinity.
5. Location: Hemoglobin is present all over the body, while myoglobin is found only in heart and muscle cells.

In summary, both hemoglobin and myoglobin are essential for oxygen transport and storage in the body. Hemoglobin is responsible for transporting oxygen in the blood, while myoglobin serves as an oxygen storage protein in muscle cells.

Comparative Table: Hemoglobin vs Myoglobin

Here is a table summarizing the differences between hemoglobin and myoglobin:

Hemoglobin and myoglobin are both heme proteins responsible for binding and transporting oxygen in the body. Hemoglobin is found in red blood cells and serves as an oxygen carrier, transporting oxygen from the lungs to the entire body. Myoglobin, on the other hand, is found in muscle cells and functions as an oxygen storage protein, providing oxygen to muscle tissue when needed.