A monomer is made up of a nitrogenous base, a five-carbon sugar, and a phosphate group bonded together. Hence, option A is correct.
A lipid is any of various organic compounds that are insoluble in water.
The smallest units of DNA are called nucleotides. These are organic molecules that serve as building blocks of DNA and RNA. They are monomers or subunits of nucleic acids like RNA and DNA. It is made up of a nitrogenous base, deoxyribose (five-carbon sugar), and at least one phosphate group.
They serve an important role in the metabolism of cells because they carry packets of energy in the form of nucleoside triphosphates (e.g. ATP, GTP, CTP, and UTP). They also play an important factor in cell signalling through enzymatic reactions and productions.
Hence, A monomer is made up of a nitrogenous base, a five-carbon sugar, and a phosphate group bonded together.
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