Which nitrogenous base is unique only to DNA? adenine

cytosine

guanine

thymine

Thymine is the nitrogenous base that is unique only to DNA.

NUCLEIC ACIDS:

Nucleic acid are biological molecules that store and transmit genetic information in living cells. The two nucleic acids are RNA and DNA. DNA and RNA are structurally made up of nucleotides that contain nitrogenous bases, phosphate groups and pentose sugar. The four nitrogenous bases are Adenine, Cytosine, Guanine and Thymine/Uracil. Thymine is only present in DNA while Uracil is only present in RNA. Other nitrogenous bases can be found in both nucleic acids. Therefore, Thymine is the nitrogenous base that is unique only to DNA.

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