Biology / Unit 2 Bio 0305 short lesson, about 20 seconds
Flagella and Cilia
Captions available
The idea
Flagella are long, few-in-number, hair-like structures that move an entire cell; cilia are short and numerous, moving the whole cell or surface substances.
In practice
A single flagellum propels a sperm cell, while dense cilia lining the respiratory tract sweep trapped particles toward the nostrils.
Where people slip
Despite differing in length and number, both share the same internal "9 + 2" microtubule arrangement.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
Unlocks
- Nothing yet depends on this.
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