a eukaryotic flagellum is different from that of a bacterial flagellum

Sure, here's a step-by-step comparison of a eukaryotic flagellum and a bacterial flagellum:

1. Structure:

   • Eukaryotic Flagellum: It is a complex structure made up of microtubules in a '9+2' arrangement. This means there are nine pairs of microtubules surrounding two central ones.
   • Bacterial Flagellum: It is simpler and composed of the protein flagellin. It doesn't have the '9+2' structure.

2. Movement:

   • Eukaryotic Flagellum: It moves in a wave-like manner, similar to the motion of a whip.
   • Bacterial Flagellum: It rotates like a propeller.

3. Assembly:

   • Eukaryotic Flagellum: It is assembled from the base towards the tip.
   • Bacterial Flagellum: It is assembled from the tip towards the base.

4. Energy Source:

   • Eukaryotic Flagellum: It uses ATP as the energy source for movement.
   • Bacterial Flagellum: It uses a flow of H+ or Na+ ions across the bacterial membrane for energy.

5. Location:

   • Eukaryotic Flagellum: It is enclosed within the cell's plasma membrane.
   • Bacterial Flagellum: It is an extension of the cell wall and membrane.

6. Function:

   • Eukaryotic Flagellum: Apart from locomotion, it also plays a role in sensory functions.
   • Bacterial Flagellum: Its primary function is locomotion.

These differences arise due to the fundamental differences between eukaryotic and prokaryotic cells.