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With nearly two hundred questions covering a wide range of more or less relevant areas of avian flu, we will try to provide answers to many questions and fears aroused by the Influenza-virus A (H5N1). This presentation which has been created in the form of questions and answers has been motivated by a desire for originality, and the willingness to create a thesis both entertaining and educational. To which family do these viruses belong? The influenza viruses belong to the genus (or type) Influenza-virus, which is a part of the Orthomyxoviridae family. What is the structure of these viruses? These virus particles are enveloped by a lipid bi-layer, which is often spherical and sometimes filamentous, ranging in diameter from 80 to 120 nm. They are studded with spicules formed by the surface glycoproteins, and their segmented genome is composed of ribonucleic acid (RNA) of single-stranded negative polarity. What kinds of surface glycoproteins are present? The Influenzavirus type A and B have two surface glycoproteins, hemagglutinin and neuraminidase. The hemagglutinin (HA or H), which represents about 40% of the surface glycoproteins, is formed by the association of two polypeptide subunits, HA1 and HA2, linked by a disulfide bridge. The combination of three monomers of HA forms a spike on the surface of the virus particle. The HA performs a hemagglutinating activity (by binding to red blood cells, it causes their agglutination) and provides for the fixation and penetration of the virus. This is done via the attachment of the virus to the sialic acid membrane with the glycoproteins of ciliated epithelial cells of the respiratory tree. HA1 is responsible for specific binding of virions to the cellular receptors, and HA2 is responsible for the fusion of the envelope with the membrane of the host cell.