DNA is a polymer, which means that it is made up of many repeating single units (monomers). What are the monomers called? The backbone of the DNA molecule is made up of two components. What are they?
The Correct Answer and Explanation is:
The monomers of DNA are called nucleotides. A nucleotide is composed of three parts: a phosphate group, a sugar molecule (deoxyribose in DNA), and a nitrogenous base. There are four different nitrogenous bases in DNA: adenine (A), thymine (T), cytosine (C), and guanine (G). These bases pair in a very specific manner: adenine pairs with thymine, and cytosine pairs with guanine, forming the rungs of the DNA ladder.
The backbone of the DNA molecule is made up of phosphate groups and deoxyribose sugars. The phosphate groups and sugars are connected by covalent bonds, forming a long chain that runs along the outside of the DNA molecule. This structure is referred to as the “sugar-phosphate backbone.” The nitrogenous bases extend from the backbone, and they pair with complementary bases from another strand of DNA to form the double helix structure.
Each nucleotide is linked to the next by a phosphodiester bond, which forms between the phosphate group of one nucleotide and the sugar of the adjacent one. This creates the long, stable chain of nucleotides that is crucial for the integrity of the DNA molecule. The two strands of DNA are held together by hydrogen bonds between the complementary base pairs, which is essential for the double helix structure. The sequence of these base pairs carries genetic information, which is used to guide the synthesis of proteins and control the functions of living organisms.
The double-stranded nature of DNA allows it to be easily copied during cell division, ensuring the transmission of genetic information from one generation to the next. This structural and functional organization is central to the processes of heredity and evolution.
