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.
The complement system is an enzyme cascade that helps defend against infection. Many complement proteins occur in serum as inactive enzyme precursors (zymogens); others reside on cell surfaces.The complement system bridges innate and acquired immunity by.Augmenting antibody (Ab) responses and immunologic memory.omplement components have other immune functions that are mediated by complement receptors (CR) on various cells. CR1 (CD35) promotes phagocytosis and helps clear immune complexes. CR2 (CD21) regulates Ab production by B cells and is the Epstein-Barr virus receptor.