Symmetry in Biology

Dictionary definition of Symmetry in biology.

Symmetry – “Correspondence of parts (in terms of form, size, distribution, or arrangement) on opposite sides of a dividing plane or on sides around an axis of an organims”

Biologists use this trait as a classifying factor on describing different organisms. It is also very important in taxonomy, physiology, medicine, drug discovery, virology, microbiology, and molecular biology.

In biology, there are three general kinds of symmetry.

First is bilateral symmetry where you can divide your organism in a “left” and a “right” part, using an axis, and when you compare these parts they’ll look similar (wow). This is very common in vertebrates.

Second is, radial symmetry, where given a central axis, you can divide your organism into many (usually around 4-8) parts and these parts will look the same, like pie or a pizza. Usually echinoderms and cnidarians.

Third is, spherical symmetry, where you can divide you organism from the center. Examples are some viruses, sea invertebrates and bacteria.



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