What are flagella used for in single-celled organisms?

Flagella are primarily used for movement in single-celled organisms. These whip-like structures extend from the cell body and rotate or undulate, allowing the organism to propel itself through liquid environments, such as water. This mobility is crucial for navigating towards nutrients, escaping predators, or finding suitable habitats.

In various single-celled organisms, like bacteria, protists, and some sperm cells in more complex organisms, flagella facilitate locomotion that is essential for survival and reproduction, even though they are not directly involved in the reproductive process or in the absorption of nutrients. Thus, movement is the primary function of flagella in these organisms, emphasizing their role in enabling the dynamic and adaptable nature of single-celled life.