In bacterial motility (prokaryotic cell biology), what is the correct term for a cell that possesses a single flagellum located at one pole (i.e., a single polar flagellum)?

Introduction / Context:
Descriptions of flagellar arrangement are classic identification clues in microbiology. Flagella can be distributed in patterns that correlate with how bacteria swim and how they are described in lab reports. This question asks for the precise term used when a single flagellum is found at one pole of a bacterial cell.

Given Data / Assumptions:

• The organism has one flagellum.
• The flagellum is positioned at a cell pole (polar location).
• Standard nomenclature for flagellar arrangement is being used (monotrichous, lophotrichous, amphitrichous, peritrichous).

Concept / Approach:
Flagellar terms are based on number and placement. Monotrichous means one flagellum, typically polar. Lophotrichous indicates a tuft of flagella at one pole. Amphitrichous indicates one flagellum at each of two poles. Peritrichous (not listed here) means flagella distributed around the cell surface.

Step-by-Step Solution:

Verification / Alternative check:
Common textbook examples include Vibrio cholerae, which is typically monotrichous, aiding rapid darting motility in liquid media.

Why Other Options Are Wrong:
Lophotrichous: Tuft at one pole, not a single flagellum. Amphitrichous: One flagellum at each pole (two total). None of these: Incorrect because a correct term (monotrichous) exists.

Common Pitfalls:
Confusing lophotrichous with monotrichous because both are polar; remember “mono-” unequivocally indicates a single flagellum.

Final Answer:
monotrichous