Flagellumok

Flagellumok is the Hungarian plural for flagellum; in English the equivalent term is flagella. Flagella are slender, whip-like organelles that propel cells through liquids and, in some species, serve as sensory antennas. They occur in bacteria, archaea, and many eukaryotic cells.

Bacterial flagella are extracellular filaments composed of a protein called flagellin, connected to a basal body that spans the cell envelope. The basal body contains a motor that uses the proton motive force (or, in some species, a sodium gradient) to rotate the filament. Rotation creates propulsion, enabling swimming and chemotaxis. Flagella may be distributed around the cell in monotrichous (one), lophotrichous (tufts), amphitrichous (both ends), or peritrichous (surface) patterns.

In eukaryotes, flagella are composed of cytoskeletal microtubules arranged in a 9+2 axoneme and powered by dynein motors that bend the structure. Unlike bacterial flagella, these flagella usually beat rather than rotate, moving the cell or directing water flow past a surface. Eukaryotic flagella are generally longer and less numerous and are common on certain protozoa, many algae, and in male gametes (sperm).

The study of flagella informs understandings of motility, sensory signaling, and the evolution of molecular motors. Flagellar function affects nutrient foraging, colonization, and virulence in pathogenic bacteria. In biotechnology and synthetic biology, flagellar motors serve as models for nanoscale machinery and as potential components in micro-robotics.