Definition Cilia are short, hair like appendages extending from the surface of a living cell. Flagella are long, threadlike appendages on the surface of a living cell.
2 Number Numerous Less in Number
3 Length Short and hair like organelle (5-10µ) Long wipe like organelle (150µ)
4 Occurrence Occurs throughout the cell surface. Presence at one end or two ends or all over the surface.
5 Cross section Nexin arm present. Nexin arm absent
6 Density Many (hundreds) per cell Few (less than 10) per cell
7 Beating Cilia beat in a coordinated rhythm either simultaneously (synchronous) or one after the other (metachronic). They beat independent of each other.
8 Motion Rotational, like a motor, very fast moving Wave-like, undulating, sinusoidal, slow movement compared to cilia
9 Found in Eukaryotic cells Eukaryotic and prokaryotic cells
10 Energy Production Cilia use ‘kinesin’ which has an ATPase activity that produces energy to perform the movement. Flagella are powered by the proton-motive force by the plasma membrane.
11 Functions Helps in locomotion, feeding circulation, aeration, etc. Help mainly in locomotion only.
12 Examples Cilia present in Paramecium Flagella present in Salmonella