Flagellum Structure and Function

The video explains how bacteria use flagella to move, detailing the structure and function of flagellar components. It covers the flagellar motor, powered by a proton gradient, and the assembly process involving various proteins. The mechanism of rotation, though not fully understood, is discussed, along with the assembly of the flagellum from the inner membrane to the extracellular portion. The video concludes with the final assembly stages and the helical structure of the filament.

How do Rota cells differ from E. coli cells in terms of flagella?

• Rota cells have no flagella, while E. coli cells have multiple.

• Rota cells have multiple flagella, while E. coli cells have one.

• Both Rota and E. coli cells have the same number of flagella.

• Rota cells have one flagellum, while E. coli cells have multiple.

What are the three main components of a flagellum?

• Filament, hook, and basal body

• Filament, rotor, and stator

• Hook, rotor, and stator

• Basal body, rotor, and filament

What powers the rotation of the flagellar motor?

• ATP hydrolysis

• Proton gradient

• Electron transport chain

• Sodium gradient

Which proteins are involved in the proton conductance of the flagellar motor?

• L and P rings

• Mo A and Mo B

• Cat proteins

• Fle F and Fle G

What is the role of the MS ring in flagellum assembly?

• It anchors the flagellum to the cell wall.

• It forms the rotor of the flagellum.

• It initiates the assembly of the flagellum.

• It powers the rotation of the flagellum.

Which proteins make up the rotor of the flagellum?

• Fle G, Fle M, and Fle N

• Mo A and Mo B

• L and P rings

• Cat proteins

What is the function of the L and P rings in gram-negative bacteria?

• They power the rotation of the flagellum.

• They initiate the assembly of the flagellum.

• They act as a bearing for the rod.

• They form the rotor of the flagellum.

How do filament proteins reach the distal end during assembly?

• They are transported by vesicles.

• They move through the hollow channel inside the filament.

• They are pushed by the rotor.

• They are assembled directly at the distal end.

What guides the assembly of hook proteins?

• The rotor

• The hook cap

• The L ring

• The MS ring

Approximately how many subunits can a complete filament consist of?

• 5,000 to 10,000

• 10,000 to 15,000

• 30,000 to 40,000

• 20,000 to 30,000