Final answer:
Cilia are short, numerous, and beat rapidly to aid in motility or particle movement, while flagella are longer and fewer in number, moving in a bend-like motion. Both are composed of a 9+2 array of microtubules and are found in eukaryotic cells. Prokaryotic flagella, while also for movement, differ structurally and functionally from their eukaryotic counterparts.
Step-by-step explanation:
Cilia and flagella are cell structures that aid in locomotion and are prominent in certain eukaryotic cells. These two structures, though similar in function, vary significantly in their physical attributes and occurrence. Cilia are short, numerous, and can cover the entire surface of the cell, they have a rapid and flexible waving motion used not only for movement but also for feeding and moving extracellular particles. On the other hand, flagella are much longer and usually present as singly or a few per cell, using a bending motion to propel the cell. Both cilia and flagella have a structural composition described as a 9+2 array of microtubules, with nine pairs surrounding two single microtubules in the center, however, they differ in their motility patterns.
Contrary to the statement in the question, both cilia and flagella are found in eukaryotic cells, not exclusively one or the other. Prokaryotic cells also possess flagella, but these are structurally different from those in eukaryotic cells. Prokaryotic flagella are made of the protein flagellin and rotate like a propeller, whereas eukaryotic flagella have a complex arrangement of microtubules and dynein and move in a wave-like motion.
In summary, it’s the structural differences and unique motion patterns that distinguish cilia from flagella, not their presence in prokaryotic or eukaryotic cells. Both cilia and flagella serve similar functions across different cell types but have evolved distinctly to suit specific cellular needs.