Final answer:
Cilia and flagella are eukaryotic cell organelles with a "9 + 2 array" of microtubules, which is essential for their movement. Cilia, being shorter, often serve additional functions like feeding and sensation, while flagella are mainly for locomotion.
Step-by-step explanation:
Cilia and flagella are locomotor organelles found in eukaryotic cells that are crucial for movement and other functions. They have a distinct structural feature known as a "9 + 2 array" of microtubules. This refers to a configuration of microtubule doublets arrayed in a circle of nine pairs, with two microtubules at the center. They utilize motor proteins, dynein, and kinesin, to facilitate the sliding of microtubules, which results in the bending and the movement of the organelle.
Cilia are typically shorter and more numerous than flagella and can function in motility, feeding, and sensation. A key structural base for these organelles is the basal body, which anchors the cilium or flagellum to the cell. Eukaryotic flagella are structurally different from their prokaryotic counterparts; the latter being rigid and rotational, while the former are whip-like and flexible. Despite these differences, both cilia and flagella serve similar functions such as locomotion in various eukaryotic organisms.