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.
The DNA double helix is held together by two types of bonds, covalent and hydrogen. Covalent bonds occur within each linear strand and strongly bond the bases, sugars, and phosphate groups (both within each component and between components). Hydrogen bonds occur between the two strands and involve a base from one strand with a base from the second in complementary pairing. These hydrogen bonds are individually weak but collectively quite strong. 3. A primer is a short segment of RNA that is synthesized by primase using DNA as a template during DNA replication.