Bacteria with a tuft of flagellae at one end are called -

Flagella They are long unbranched sinuous filaments which are organs of locomotion . Each flagellum consist of 3 distinct pa the filament the hook and the basal body.The filament is external to the cell and connected to the hook at the cell surface . Structure: The Hook-Basal body poion is embedded in the cell envelope . They are antigenically different. Flagella are made up of protein(flagellin). Though flagella of different bacteria have similar composition they antigenically different.flagellar antibodies are not protective but are usful in sero diagnosis . The presence or absence of flagella and their number and arrangement are characteristic of different genere of bacteria. Flagella may be arranged all round the cell (peritrichous) as a typhoid bacilli, or situated at one or both ends of the cell (polar). Polar flagella may be single (monotrichous) as in cholere vibrio, in tufts (lophotrichous)as in spirilla or with flagella at both poles(amphitrichous) Ref:C.P.Baveja pg no.17-18