What do a human, a rose, and a bacterium have in common? Each of these things — along with every other organism on Earth — contains the molecular instructions for life, called deoxyribonucleic ...

Shortly after, Watson and Crick made a crucial advance when they proposed that the DNA molecule was made up of two chains of nucleotides paired in such a way to form a double helix, like a spiral ...

Science is rarely straightforward. Many times, scientists embark on a study looking for evidence for a particular hypothesis, ...

Combinations of these atoms form the sugar-phosphate backbone of the DNA -- the sides of the ladder, in other words. Other combinations of the atoms form the four bases: thymine (T), adenine (A ...

A second major difference between the two substances is that RNA is made in a single-stranded, nonhelical form. (Remember, DNA is almost always in a double-stranded helical form.) Furthermore ...

Whether this bizarre form of DNA existed in cells and had any function, and what that might be, was hotly debated for nearly half a century. But research has recently confirmed its biological ...