Cilia & Flagella
Source:http://www.cartage.org
Cilia and Flagella are the hairlike organelles that are extended from the surface of the cell. Their purpose is to assist in movement. Both cilia and flagella have similar structure. They are both composed of nine pairs of microtubules arranged around a central pair. When the hairlike organelles are short and are present in large numbers on a cell are known as cilia. Many of the external surfaces of unicellular organisms are covered in these short hairlike organelles, cilia. The movement of the cilia helps the movement of tiny organisms through water. Cilia isn't just found in unicellular organisms they are also in multicellular organisms, where they are found on the surface. Cilia for an example sweeps and traps the debris from the air a person inhales. Flagella are the longer hairlike organelles, that are less in number. Flagella are found on the cell as well, and by whipping back and forth they move unicellular organisms and multicellular organisms.