Another micrograph of the cell surface showing a number of cilia. These must be organized functionally so the cilia beat in a wave. Return to Menu Centrioles and Basal Bodies Cilia and flagella are organized from centrioles that move to the cell periphery. Basal bodies control the direction of movement of the cilia. This can be shown experimentally.
Centrioles control the direction of cilia or flagella movement.
Note the experiment in your text that describes how the direction of movement was changed. Paramecium has parallel rows of cilia all aligned so that they will beat in the same direction. The cells passed on the change to future generations even though this was not a genetic alteration. See you text, page 820, for more information. Return to Menu Centriole structure Like Cilia and Flagella, Centrioles are also made of microtubules.