An organ or group of specialized cells in the body that produces and secretes a specific substance, such as a hormone
A nucleic acid is made of nucleotides, and nitrogenous bases are a part of a nucleotide.
DNA is a nucleic acid. The nucleotides in DNA are made up of a sugar (deoxyribose), a phosphate group, and one nitrogenous base (which will be either adenine, guanine, cytosine, or thymine).
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