Flagellum (Cilium) AJ SCIELZO

Prokaryotic Flagella  Long, threadlike structures protruding from the outside surface of the cell  Main function is movement  Prokaryotic flagella are protein fibers that extend from the cell  Multiple depending on the species

Prokaryote cont’d  Using the flagella, some bacteria can “swim” up to 70 cell lengths per second.  The bacteria rotates the flagella like screws to move.  The rotary motor uses the energy stored in a gradient that transfers protons across the plasma membrane to power the movement of the flagellum.  This same process is used in the eukaryotic mitochondria and chloroplasts by an enzyme that synthesizes ATP.  Some protists have cilia which are basically smaller scale flagellum

Prokaryotic Cells Flagellum

Eukaryotic Flagella  A lash-like appendage sticking out of the cell  Primary function is locomotion, but is also a sensory organelle reacting to chemicals and temperature outside the cell.  Example: sperm cell

Prokaryotic vs Eukaryotic Flagellum  The flagella is unique and differs from prokaryotic to eukaryotic.  They differ in protein composition, structure, and methods of propulsion.

Methods of Propulsion Prokaryotic  They use their flagellum in a screw- like motion and propel the cell that way. Eukaryotic  These cells move the flagellum back and forth lashing it around to propel the cell.

Flagella v Cilia