Lymphedema (lymphoedema in British English), also known as lymphatic obstruction, is a condition of localized fluid retention and tissue swelling caused by a compromised lymphatic system, which normally returns interstitial fluid to the thoracic duct and then the bloodstream.ymphedema (lymphoedema in British English), also known as lymphatic obstruction, is a condition of localized fluid retention and tissue swelling caused by a compromised lymphatic system, which normally returns interstitial fluid to the thoracic duct and then the bloodstream.
1 A polypeptide is a single linear chain of many amino acids, held together by amide bonds. 2  A protein is one or more polypeptide (more than about 50 amino acids long).  An oligopeptide consists of only a few amino acids (between two and twenty).
The primary level of structure in a protein is the linier sequence of amino acids, formed by a condensation reaction (and therefore the abstraction of water) in protein synthesis. Each amino acid residue is then bonded via peptide bonds.herefore the amide planes define the polypeptide backbone. The secondary level of structure in a protein is the regular folding of the regions of the polypeptide chain. The two most common types are the alpha-helix and the beta-pleated sheet. Both myoglobin and haemoglobin are mostly made up from alpha-helices.