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 has the potential to be extremely damaging to host tissues, meaning its activation must be tightly regulated. The complement system is regulated by complement control proteins, which are present at a higher concentration in the blood plasma than the complement proteins themselves.5b initiates the membrane attack pathway, which results in the membrane attack complex (MAC), consisting of C5b, C6, C7, C8, and polymeric C9. MAC is the cytolytic endproduct of the complement cascade; it forms a transmembrane channel, which causes osmotic lysis of the target cell.