For the following fragment of DNA determine 5ACGTAGAGTGCTC3

For the following fragment of DNA, determine: 5\'-ACGTAGAGTGCTC-3\' 3\'-TGCATCTCACGAG-5\' the number of hydrogen bonds present.

Solution

Step I: To get an idea of the number of hydrogen bonds between bases

Number of hydrogen bonds between AT = 2 hydrogen bonds

Number of hydrogen bonds between GC = 3 hydrogen bonds

Step II: Observe the fragment carefully and identify the bonds

Six AT bonds and Six CG bonds

Step III: Calculate

6x2 + 6x3 = 30

So number of hydrogen bonds present is 30