What are the slender, hairlike extensions used by certain bacteria for movement called?

The slender, hairlike extensions used by certain bacteria for movement are called flagella. Flagella are long, whip-like structures that rotate and propel the bacterial cell through its environment, allowing the bacteria to move toward nutrients or away from harmful substances. This mode of locomotion is essential for many bacteria, enabling them to navigate through liquids, which is a critical aspect of their survival and ability to infect hosts.

Pseudopodia, on the other hand, are temporary projections used by some microorganisms, including amoebas, for movement and feeding. Cilia consist of shorter, hair-like structures that also help in movement but are found in a different context, often on eukaryotic cells rather than bacteria. Fimbriae are short, bristle-like fibers that allow bacteria to adhere to surfaces but do not assist in movement. Understanding these distinctions helps clarify the unique functions of different bacterial structures.