Draw the chemical structure of the three components of a nucleotide, and then link the three together. What atoms are removed from the structures when the linkages are formed?

Video transcript

Hi everyone. Let's take a look at this practice problem together. Two nucleotides are linked together through phosphor di ester linkage. How many phosphor di ester linkages are present in a DNA molecule that contains 48 nucleotides in each strand. So calculate the number of phosphor di ester bonds. And I'm going to abbreviate phosphor o di ester bonds with P. D. So there is an equation, it's the number of phosphor di ester bonds equals two n -2 and N equals the number of base pairs. So let's look at a quick example of this. We've got an example here. We've got this double strand DNA three guanine bonded with three sided scenes. So six nucleotides total. That's three base pairs. And so if we plug that in two times 33 base pairs minus two, that's going to equal six minus two. Which equals four phosphor di ester bonds and that is how many is present. And so let's use that equation and figure it out for our DNA molecule. So the number of phosphor diaspora bonds equals two N minus two. And is the number of base pairs we are told there are 48 nucleotides in each strand so there are 48 base pairs total. So two times 48 minus two. That would equal 96 minus two equals 94. And so there would be 94 phosphor di ester bonds in our DNA molecule? And that answer is c 94. Alright, everyone. I hope you found this helpful. And I'll see you soon for the next practice problem