An unrolled DNA molecule has two strands twisted around each other. The double helix is a description of this shape. Today this shape is often used, as a symbol for DNA. The DNA double helix is dextrorotatory. If you look at it as if it were a slide, the strand would curve in a clockwise direction.
What is the DNA Double Helix?
When you unroll a chromosome completely, you get to see the well-known spiral structure of DNA. This is also called the double helix and consists of two strands that twist around each other. The double helix is the world famous form of DNA
The connection between the strands
The strands are made up of all loose links, nucleotides (link to other article), which are attached to each other and thus form a very long chain. A nucleotide consists of three parts: a deoxyribose group, a phosphate group and a base. The first two form the backbone of the chain and the base connects to the complementary (complementary) base of the other DNA strand. Through the connections of the bases, the so-called base pairs, DNA forms its characteristic double helix.