Symmetry: Quick Facts

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Photos

Illustration comparing two invertebrate body plans: a starfish with multiple lines showing radial symmetry on the left, and a fly with a single line showing bilateral symmetry on the right.

Bright orange and purple sea urchin with long spines resting on a seagrass bed in shallow water, Malapascua, Cebu, Philippines.

Translucent moon jellyfish with four distinct circular patterns in its center floats against a dark background.

A male moose with large antlers stands facing forward in tall grass and autumn foliage in Jackson, Wyoming.

bilateral symmetry

radial symmetry

Cluster of bright red and purple Hummingbird Fuchsia flowers hang from a branch amid green leaves, with a blurred natural background.

bilateral symmetry

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Topics

spherical symmetry bilateral symmetry biradial symmetry mesaxonic condition radial symmetry Pi in nature oral-aboral axis transverse axis sagittal axis zygomorphic flower Metabolism death coloration Sex sleep photosynthesis Biological development aging mimicry nutrition

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Morphology: Body plan and symmetry

greylag. Flock of Greylag geese during their winter migration at Bosque del Apache National Refugee, New Mexico. greylag goose (Anser anser)

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