In
biology,
bilateral symmetry is a characteristic of multicellular organisms, particularly
animals. A bilaterally symmetric organism is one that is symmetric about a plane running from its frontal end to its caudal end (head to tail), and has nearly identical right and left halves. Most animals are bilaterally symmetric, including humans. The exceptions are
sponges (no symmetry),
jellyfish and
ctenophores (
radial symmetry), and
echinoderms (partial radial symmetry).
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