In fact, cysteines are the only amino acids capable of forming covalent bonds, which they do with their particular side chains. Because of side chain interactions, the sequence and location of amino acids in a particular protein guides where the bends and folds occur in that protein (Figure 1).
gas exchange between the pulmonary blood and lungs where oxygen from fresh air in lungs moves into the blood and excess CO2 from the blood moves into the lungs.xygen and carbon dioxide that are transported to and from the lungs and tissue cells where oxygen is pumped throughout the body is CO2 is pumped back into the lungs.
Medical Definition of Gas exchange. Gas exchange: The primary function of the lungs involving the transfer of oxygen from inhaled air into the blood and the transfer of carbon dioxide from the blood into the exhaled air. Last Editorial Review: 5/13/2016.