Helix

The staircase in the Vatican Museums. This shows a helix.
Spiral of a climber plant, also a helix

In math, a helix is a curve in three dimensions. It looks a bit like a spiral. Each helix has a line called its axis that goes through its center. The helix has a constant angle to this line. A helix can fit around the outside of a cone with the same axis and angle. Helices are often seen in nature and the sciences.

A well known helix is the shape of a DNA molecule. It is called the double helix because its shape has two helices around each other that share the same axis. Many proteins also curl into helix shapes when they fold.

  1. ↑ "Double Helix". www.genome.gov. Retrieved 2026-06-15.
  2. ↑ Barlow, D. J.; Thornton, J. M. (1988-06-05). "Helix geometry in proteins". Journal of Molecular Biology. 201 (3): 601–619. Bibcode:1988JMBio.201..601B. doi:10.1016/0022-2836(88)90641-9. ISSN 0022-2836. PMID 3418712.