2007-01-10 12:27:55 · 5 answers · asked by Dija 1 in Science & Mathematics ➔ Biology
hydrogen bonds between the A and T, C and G. Also base stacking, which is somewhat like a hydrogen bond, it keeps the helix as a helix.
The wiki has a bunch of info which seems pretty accurate.
Base stacking
Base stacking interactions between the pi orbitals of the bases' aromatic rings also contribute to stability, and again GC stacking interactions with adjacent bases tend to be more favorable. (Note, though, that a GC stacking interaction with the next base pair is geometrically different from a CG interaction.) Base stacking effects are especially important in the secondary structure of RNA; for example, RNA stem-loop structures are stabilized by base stacking in the loop region.
2007-01-10 14:30:06 · answer #1 · answered by gibbie99 4 · 0⤊ 0⤋
Hydrogen Bonds. The nitrogeneous bases have either 2 or 3 hydrogen bonds between them which hold the double helix together.
2007-01-10 20:33:21 · answer #2 · answered by jamesefm 2 · 0⤊ 0⤋
Hydrogen bonding between the base pairs holds the double helix together, and it occurs between pyrimidines and purines. Cytosine hydrogen bonds with guanine, and adenine hydrogen bonds to thymine.
In RNA, no double helix is formed because thymine is replaced by uracil, which does not hydrogen bond to adenine.
2007-01-10 20:32:48 · answer #3 · answered by John 3 · 0⤊ 0⤋
Hydrogen bonds between the complementary nitrogenous bases of the two strands.
2007-01-10 20:34:21 · answer #4 · answered by Anonymous · 0⤊ 0⤋
Hydrogen bonds.
2007-01-10 20:31:56 · answer #5 · answered by Anonymous · 0⤊ 0⤋