nuclei acid

• DNA molecule gets its name from deoxyribonucleic acid which is a type of nucleic acid. Nucleic acids are made up of polynucleotide chains which are formed by many nucleotides bonded together. Each nucleotide, the basic unit of a polynucleotide chain, is made with three parts: the phosphate, the sugar, and the nitrogenous base.

  There are four different bases in a DNA nucleotide. These bases are adenine, cytosine, guanine, thymine.
• The structure of DNA consists of two strands that wind around one another to form a double helix. The backbone of the DNA molecule is composed of alternating sugars (deoxyribose) and phosphates. Adenine always pairs with thymine, while cytosine always pairs with guanine. This pairing occurs because these bases have complementary shapes and chemical properties.
• A gene is a segment of DNA that contains instructions for making proteins or RNA molecules. Genes can be located on any chromosome and may contain multiple exons separated by introns.