Washington's Birthday, also known as Presidents' Day, is a federal holiday held on the third Monday of February. The day honors presidents of the United States, including George Washington, the USA's first president. George Washington was the first president of the United States of America.
Complement component 5 is a protein that in humans is encoded by the C5 gene.Complement component 5 is involved in the complement system. It is cleaved into C5a and C5b: 1  C5a plays an important role in chemotaxis.2  C5b forms the first part of the complement membrane attack complex.omplement component 5 is the fifth component of complement, which plays an important role in inflammatory and cell killing processes.
complement activation occurs by two different sequences, the classic and alternative pathways. The proteins of the classic pathway are termed components of complement and are designated by the symbols C1 through C9. C1 is a calcium dependent complex of three distinct proteins C1q, C1r and C1s.The proteins of the alternative pathway (collectively referred to as the properdin system) and complement regulatory proteins are known by semisystematic or trivial names.Fragments resulting from proteolytic cleavage of complement proteins are designated with lower case letter suffixes, for example, C3a.omplement activation also results in the formation of many biologically active complement fragments that act as anaphylatoxins, opsonins or chemotactic factors.