The bacterium flagellum is composed of three major structural elements. Which of the following is NOT one of these elements?

Torso

The correct answer is Option (1) - Torso

The bacterium flagellum is composed of three major structural elements:

1. Filament: This is the long, whip-like extension of the flagellum responsible for propelling the bacterium forward.
2. Hook: The hook is a flexible, curved region that connects the filament to the basal body. It acts as a flexible joint allowing movement.
3. Basal Body: The basal body is the complex structure that anchors the flagellum to the cell wall and membrane, and it is also responsible for the rotation of the flagellum.

Not one of these elements:

• Torso: The term "torso" is not a recognized structural component of the bacterial flagellum. The basal body, hook, and filament are the three main components involved in bacterial flagellar structure and function.