:''This article is about the shape. See helix (disambiguation) for other meanings.'' A helix (pl: helices), from the Greek language word ''έλικας/έλιξ'', is a twisted shape like a spring, screw or a spiral staircase. Helices are important in biology, as DNA is helical and many proteins have helical substructures, known as alpha helix. Right-handed and left-handed helices can be distinguished from each other. If you move along a helix in the direction of your right hand's thumb, and the helix turns in the direction of your right hand's fingers, then it's a right-handed helix, otherwise a left-handed one. Another way to visualize this distinction: picture the helix vertical; if the front strands move from the lower left to the upper right, then it is a right-handed helix. Note that handedness (or chirality (mathematics)) is a property of the helix, not of the perspective: you can turn a right-handed helix around and it's still right-handed. Most screws are right-handed helices. The alpha helix in biology as well as the A and B forms of DNA are also right-handed helices. The Z form of DNA is left-handed. The pitch of a helix is the length of one complete helix turn, measured along the helix axis. In mathematics, a helix is a Differential geometry of curves in 3-dimensional space. The following three equations in Cartesian coordinate system define a helix: : ''x'' = Trigonometric function ''t'' : ''y'' = Trigonometric function ''t'' : ''z'' = ''t'' Here ''t'' is a real number parameter. As ''t'' increases, the point (''x'',''y'',''z'') traces a right-handed helix of pitch 2pi about the ''z''-axis, in a right-handed coordinate system. In cylindrical coordinates (''r'', θ, ''h''), the same helix is described by: : ''r'' = 1 : θ = ''h'' Except for rotations, translation (geometry)s, and changes of scale, all right-handed helices are equivalent to the helix defined above. The equivalent left-handed helix can be constructed in a number of ways, the simplest being to negate either the x, y or z component. In music pitch space is often modeled with helixes or double helixes, most often extending out of a circle such as the circle of fifths, so as to represent octave equivalency. Curves
See other meanings of words starting from letter:
Words begining with Helix:
Helix
Helix,_OR
Helix,_Oregon
Helix-turn-helix
Helix84
Helix84
Helixblue
Helixblue
Helix_(band)
Helix_(cipher)
Helix_(comics)
Helix_(disambiguation)
Helix_(genus)
Helix_(genus)
Helix_Community
Helix_database
Helix_High_School
Helix_Nebula
Helix_nebula
Helix_piercing
Helix_player
Helix_project
Helix
:''This article is about the shape. See helix (disambiguation) for other meanings.'' A helix (pl: helices), from the Greek language word ''έλικας/έλιξ'', is a twisted shape like a spring, screw or a spiral staircase. Helices are important in biology, as DNA is helical and many proteins have helical substructures, known as alpha helix. Right-handed and left-handed helices can be distinguished from each other. If you move along a helix in the direction of your right hand's thumb, and the helix turns in the direction of your right hand's fingers, then it's a right-handed helix, otherwise a left-handed one. Another way to visualize this distinction: picture the helix vertical; if the front strands move from the lower left to the upper right, then it is a right-handed helix. Note that handedness (or chirality (mathematics)) is a property of the helix, not of the perspective: you can turn a right-handed helix around and it's still right-handed. Most screws are right-handed helices. The alpha helix in biology as well as the A and B forms of DNA are also right-handed helices. The Z form of DNA is left-handed. The pitch of a helix is the length of one complete helix turn, measured along the helix axis. In mathematics, a helix is a Differential geometry of curves in 3-dimensional space. The following three equations in Cartesian coordinate system define a helix: : ''x'' = Trigonometric function ''t'' : ''y'' = Trigonometric function ''t'' : ''z'' = ''t'' Here ''t'' is a real number parameter. As ''t'' increases, the point (''x'',''y'',''z'') traces a right-handed helix of pitch 2pi about the ''z''-axis, in a right-handed coordinate system. In cylindrical coordinates (''r'', θ, ''h''), the same helix is described by: : ''r'' = 1 : θ = ''h'' Except for rotations, translation (geometry)s, and changes of scale, all right-handed helices are equivalent to the helix defined above. The equivalent left-handed helix can be constructed in a number of ways, the simplest being to negate either the x, y or z component. In music pitch space is often modeled with helixes or double helixes, most often extending out of a circle such as the circle of fifths, so as to represent octave equivalency. Curves
See other meanings of words starting from letter:
H
HA | HB | HC | HD | HE | HF | HG | HI | HJ | HK | HL | HM | HN | HO | HP | HR | HS | HT | HU | HW | HX | HY | HZ |Words begining with Helix:
Helix
Helix,_OR
Helix,_Oregon
Helix-turn-helix
Helix84
Helix84
Helixblue
Helixblue
Helix_(band)
Helix_(cipher)
Helix_(comics)
Helix_(disambiguation)
Helix_(genus)
Helix_(genus)
Helix_Community
Helix_database
Helix_High_School
Helix_Nebula
Helix_nebula
Helix_piercing
Helix_player
Helix_project
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