The cylindrical helix can be defined as a helix traced on a vertical cylinder of revolution, or a rhumb line of this cylinder ... (1) where is the tension of the wire, the tangent unit vector, the magnetic field and I the intensity of the current; shows that the norm of the tension is constant: T = constant. Helix. Helices are important in biology, as the DNA molecule is formed as two intertwined helices, and many proteins have helical substructures, known as alpha helices. A helix (/ ˈ h iː l ɪ k s /), plural helixes or helices (/ ˈ h ɛ l ɪ s iː z /), is a shape like a corkscrew or spiral staircase.It is a type of smooth space curve with tangent lines at a constant angle to a fixed axis. A helix, sometimes also called a coil, is a curve for which the tangent makes a constant angle with a fixed line.