Each nucleotide in DNA contains one of four possible nitrogenous bases: adenine (A), guanine (G) cytosine (C), and thymine (T). Adenine and guanine are purines, meaning that their …

A nucleotide is made up of a sugar (deoxyribose), a phosphate group, and one of four nitrogenous bases: adenine (A), thymine (T), guanine (G) or cytosine (C). C and T bases, …

So, again, the purines are adenine and guanine and the pyrimidines are thymine and cytosine. And the purines and pyrimidines will always pair up with each other in this fashion. Adenine …

DNA, short for deoxyribonucleic acid, consists of nucleotides forming a double helix structure. Nucleotides contain a phosphate group, deoxyribose sugar, and a nitrogenous base. The …

DNA, short for deoxyribonucleic acid, consists of nucleotides forming a double helix structure. Nucleotides contain a phosphate group, deoxyribose sugar, and a nitrogenous base. The …

Composed of a sugar-phosphate backbone and base pairs (adenine-thymine, guanine-cytosine), DNA stores genetic information, replicates, and expresses traits. The human genome contains …

Composed of a sugar-phosphate backbone and base pairs (adenine-thymine, guanine-cytosine), DNA stores genetic information, replicates, and expresses traits. The human genome contains …

The bases, adenine, thymine, cytosine, and guanine, pair up through hydrogen bonds, creating the rungs of the DNA ladder. DNA, short for deoxyribonucleic acid, consists of nucleotides …

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Then adenine and guanine are the purines. They are a double-ringed structure. They're composed of one ring with six sides to it, and then that ring is attached to another ring that has …