Respiratory Gases
The respiratory system is involved in the transport of respiratory gases like oxygen and carbon dioxide in the blood.
Hemoglobin and myoglobin are both essential oxygen-binding proteins.
- Hemoglobin transports oxygen in red blood cells (erythrocytes). The protein has a special affinity for oxygen, known as its oxygen-carrying capacity that's influenced by several factors like temperature or pH.
- Myoglobin is an intracellular protein that stores oxygen within muscle tissue for use during exercise. It has a very high affinity for oxygen compared with hemoglobin and functions to store oxygen.
Learn the mechanisms used to transport respiratory gases with the interactive animations and diagrams below. Get a crash course in respiratory system anatomy.
Hemoglobin Molecule – Structure & Function
Hemoglobin structure in a detailed, interactive and illustrated tutorial (globin, alpha and beta subunits, porphyrin, heme groups,…etc) with colorful and simple animations about its states (relaxed & tensed).
Myoglobin Structure and Function
Myoglobin binds and stores oxygen inside of skeletal and cardiac muscle cells. The heme group consists of ferrous iron and a surrounding porphyrin ring. Two histidine molecules are associated with the heme.
Oxygen-Hemoglobin Dissociation Curve | How pH, CO and CO2 Affect it
The changes in blood plasma pH, CO and CO2 affect the oxygen-hemoglobin saturation.
Oxygen Myoglobin Dissociation Curve
If an isolated muscle fiber has been placed in a vial of deoxygenated blood. Inside the muscle fiber, each molecule of myoglobin can bind one O2. The O2-Mb bond is reversible, and the direction of the reaction is dependent on the concentration of O2 (partial pressure or pO2) in the surrounding fluids.