Cytosine Thymine Adenine Guanine

Cytosine Thymine Adenine Guanine. Chemical structure of DNA, showing four nucleobase pairs produced by eight nucleotides: adenine (A) is joined to thymine (T), and guanine (G) is joined to cytosine (C) In double stranded DNA, the guanine (G) base on one strand can form three H-bonds with a cytosine (C) base on another strand (this is called a GC base pair)

In the case of DNA, those bases are adenine, guanine, cytosine, and thymine The 3′ carbon of one nucleotide is linked to the 5′ carbon of the next via a phosphodiester bond.

(credit a: modification of work by Jerome Walker, Dennis Myts) The Structure of RNA The thymine (T) base on one strand can form two H-bonds with an adenine (A) base on the other strand (this is called an AT base pair). (B) A DNA strand containing four nucleotides with the nitrogenous bases thymine (T), cytosine (C), adenine (A) and guanine (G) respectively

. In the case of DNA, those bases are adenine, guanine, cytosine, and thymine The 5' to 3' (read "5 prime to 3 prime") directions are: down the strand on the left, and up the strand on the right.

. One copy of the human genome consists of approximately 3 billion base pairs of DNA. Two hydrogen bonds are formed between adenine and thymine, but three hydrogen bonds hold together guanine and cytosine (Figure 2.127).