Fifty years of making downwind sailing products means that we know what you need to sail off the wind, and we have a selection of poles and related fittings to do the job right for your boat. I can't imagine sailing downwind without my whisker pole. I make offshore passages for a living and I count on my Forespar* whisker pole.
Internal and external hydrogen bonds stabilize the DNA molecule. The two strands of DNA stay together by H bonds that occur between complementary nucleotide base pairs. Two hydrogen bonds occur between the adenosine and the thymine base pairs, and between the cytosine and the guanine there are three.
Base Pairing in DNA. The nitrogen bases form the double-strand of DNA through weak hydrogen bonds. The nitrogen bases, however, have specific shapes and hydrogen bond properties so that guanine and cytosine only bond with each other, while adenine and thymine also bond exclusively. This pairing off of the nitrogen bases is called complementarity.