Double helix

In geometry, a double helix (plural double helices) is two helices with the same axis, but they differ by a translation along the axis. The term is most often used in reference to the nucleic acid double helix, the main structure of nucleic like DNA and RNA.

Double Helix Media

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  Two complementary regions of nucleic acid molecules will bind and form a double helical structure held together by base pairs.

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  This is a picture of the various base parameters so that people can see the base orientations.

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  The structures of A-, B-, and Z-DNA.

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  The helix axis of A-, B-, and Z-DNA.

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  Major and minor grooves of DNA. Minor groove is a binding site for the dye Hoechst 33258.

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  Supercoiled structure of circular DNA molecules with low writhe. The helical aspect of the DNA duplex is omitted for clarity.