Rosenbergs executed. On this day in 1953, Julius and Ethel Rosenberg, who were convicted of conspiring to pass U.S. atomic secrets to the Soviets, are executed at Sing Sing Prison in Ossining, New York. Both refused to admit any wrongdoing and proclaimed their innocence right up to the time of their deaths, by the electric chair.
Bonds between linking nitrogenous bases of two DNA strands are Hydrogen bonds with 3 H-bonds connecting cytosine and guanine and 2 H-bonds connecting adenine and thymine, while the bonds between the stacking of DNA are kept in close contact via van der waals interactions.
Base pairs occur when nitrogenous bases make hydrogen bonds with each other. Each base has a specific partner: guanine with cytosine, adenine with thymine (in DNA) or adenine with uracil (in RNA). The hydrogen bonds are weak, allowing DNA to 'unzip'. This lets enzymes replicate the DNA.