Biology / Unit 10 Bio 2219 short lesson, about 20 seconds
Body Symmetry: Asymmetry, Radial, Bilateral
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The idea
An animal body shows asymmetry, radial symmetry around a central axis, or bilateral symmetry with matching left and right halves.
In practice
A sponge is asymmetrical, a sea anemone is radially symmetrical, and a crab is bilaterally symmetrical despite its unusual shape.
Where people slip
Radial symmetry suits a stationary or drifting lifestyle, sensing equally in all directions — not a precursor stage to bilateral symmetry.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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