Overview
This lecture explains the different types of bacterial flagella arrangements, their terminology, and their role in bacterial movement.
Functions and Importance of Flagella
- Flagella are appendages used by bacteria for movement.
- Bacterial motility with flagella is like swimming through a thick substance due to their small size.
Types of Flagella Arrangements
- Bacteria are categorized by the presence and arrangement of flagella.
- Atrichous bacteria lack flagella entirely.
- Polar flagella are located at one or both ends of the cell.
- Monotrichous bacteria have a single flagellum at one end (mono = one).
- Amphitrichous bacteria have flagella at both ends (amphi = both).
- Lophotrichous bacteria have a tuft (cluster) of flagella at one end.
- Peritrichous bacteria have flagella distributed all over their surface.
Key Terms & Definitions
- Flagella — long, whip-like structures that provide motility to bacteria.
- Atrichous — bacteria without any flagella.
- Polar — general term for flagella present at the ends of the cell.
- Monotrichous — a single flagellum at one end of the cell.
- Amphitrichous — flagella at both ends of the cell.
- Lophotrichous — a cluster (tuft) of flagella at one end.
- Peritrichous — flagella distributed over the entire surface.
Action Items / Next Steps
- Review and memorize the definitions and examples of different flagellar arrangements.