Many types of cells possess flagella, hair-like structures primarily used for movement. These whip-like appendages are found across a wide range of organisms.
Eukaryotic Cells with Flagella
- Protozoa: The Mastigophora group of protozoa are characterized by their flagella. [Reference 1]
- Gametes (sex cells): Flagella are found on the gametes (sperm cells) of algae, fungi, mosses, slime molds, and animals. [Reference 1]
- Specialized cells: Some animal cells, including many human cells, have a flagellum. [Reference 3] For example, sperm cells use flagella for motility.
Prokaryotic Cells with Flagella
- Bacteria: Most motile bacteria use flagella for movement. [Reference 1] Examples include Escherichia coli which uses its flagella for adhesion and invasion. [Reference 5] The Lyme disease spirochete, Borrelia burgdorferi, also utilizes periplasmic flagella. [Reference 7] Even archaea, like Pyrococcus furiosus, possess flagella. [Reference 9]
Function of Flagella
Beyond locomotion, flagella play other roles:
- Water currents: In sponges and coelenterates, flagellar motion creates water currents crucial for respiration and circulation. [Reference 1]
- Adhesion: In some bacteria, flagella contribute to adhesion to surfaces and host cells. [Reference 5]
It's important to note that flagella in prokaryotes (bacteria and archaea) differ structurally from those in eukaryotes (plants, animals, fungi, protists). While both serve primarily for motility, their composition and mechanism of action vary significantly. The presence or absence of flagella can be used as a characteristic to classify and identify various organisms.
