Pili and fimbriae G-", short, fine, hairlike appendages that are not involved in motility Fimbriae/fimbria: 1000piece/cell adhesion to host epithelium Sex pili/pilus: 1-10piece/cell, sexual conjugation, they are genetically determined by sex factors or conjugative plasmids and are required for bacterial mating. Receptors of some bacterial viruses.Pili and fimbriae G-, short, fine, hairlike appendages that are not involved in motility. Fimbriae/fimbria:1000piece/cell, adhesion to host epithelium Sex pili/pilus: 1-10piece/cell, sexual conjugation, they are genetically determined by sex factors or conjugative plasmids and are required for bacterial mating. Receptors of some bacterial viruses