5 Nitrogenous Bases

by Jason Amores Sumpter
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So now that we know that one of the components of a single nucleotide monomer is the nitrogenous base in this video, we're gonna focus on the five nitrogenous bases. And so once again, there are five different nitrogenous bases, and these five nitrogenous bases can be grouped together as either pi remedies or as pure ins. And so the pie remedies are single ringed molecules, whereas the pure ings are double ringed molecules. And so, if we take a look at our image down below over here on the left hand side, notice that we're showing you the nitrogenous bases which can once again be grouped into these two groups. The pie remedies which we have over here on the left hand side, and the pure ings which we have over here on the right hand side and notice that the pie remedies, as we mentioned up above, are all single ringed molecules, so they only have one single ring, whereas the pure ings over here are all double ringed molecules. So they all have two rings. Like what we see here now. Also, these air called nitrogenous bases for a reason because they have plenty of nitrogen atoms as you can see, what I'm highlighting right here. All of these nitrogen atoms makes these bases pretty nitrogenous, and that's why we call them nitrogenous bases. Now it's also important to note that each of these nitrogenous bases has a name. And so you can see we have cytosine timing and you're so are the pie remedies. And then we have adding and guanine as the pure ings. And so notice that each of these nitrogenous bases names has a unique first letter. And so, for instance, side of scenes See, here it's first letter is unique. First letter. It's the only one that starts with a C and so we can use the first letter C to abbreviate side of scene now. I mean, it's unique. First letter is t yourselves unique. First letter is you. Adnan's unique first letter is a and guanine is unique. First letter is she And so we can abbreviate these, uh, nitrogenous bases just by using the one letter. Now notice that when we introduced by remedies up above that, we made the why here in pi remedies interactive for you guys to fill out yourselves as you watch this video and the reason that we're emphasizing this. Why here is because notice that most of the pie remedies which have a Y in it also have a y in them themselves. So sido scene and thigh mean have wise in them which make them pie remedies and notice that the pure ings such as adding and guan ing they do not have a Y in them. And so they're gonna be batch over here. And really the Onley exception to this. Why is gonna be the euro sell your cell is a pie remedying even though it doesn't have a why. But if you could just remember this one exception, then that will help you batch these nitrogenous bases into the correct groups Now, which will also notice is down below the image. We have this memory tools to also help you group and batch these, uh, nitrogenous bases. So when you think of pie remedying that kind of sounds like pyramids. And when you think about pyramids, you think about the Egyptian pyramids. And of course, we all know that underneath the Egyptian pyramids there are creepy tombs under those pyramids. And so here we have an image of the creepy tombs under the Egyptian pyramids. And so you can think that, uh, the sea and creepy is for the C inside of seen. The tea and tombs is for the tea and timing and, of course, the U and unders for the you and you're a cell. And so, by remembering pie remedies thinking about pyramids, you'll think about the creepy tombs under the pyramids and you'll be able to group these nitrogenous spaces. No problem. Now, on the other hand, the pure ings. On the other hand, all you gotta do is think about pure as gold. So here we've got this guy has got some gold in his hand and he's thinking pure is gold. And so what you can see here is that the A and as is for the A and add Ning. And of course, the G and gold here is for the G and guanine. And so, by remembering that periods are pure as gold, you'll be ableto determined. These, uh, adding and guanine are appearing. No problem now. Another important thing to note here is that timing is a nitrogenous base that is uniquely Onley found in D N A. Whereas you're So on the other hand is a nitrogenous base that is uniquely found Onley in our DNA. And so in our DNA structure, what we'll see is that all of the teas are gonna be replaced with use. And so use once again our specific for Onley in RNA, whereas tease air specific for Onley in DNA. So that's an easy way for us to be able to identify if a strand is DNA or RNA just by looking to see if teas or used are being used. Now this leads us to talk a little bit about DNA structure here because in DNA structure, the nitrogenous bases on different DNA strands are going to base pair together. And so the base pairing works in this fashion, where Adnan's or a czar always going to pair with thigh means or teas and side of scenes or seas are always going to pair with guanine or G's. And so what you can see is that a pure ing is always going to be paired up with a pie remedy. Eso A's pair with teas and then once again, uh, the pyre emitting of citizen is always gonna be paired up with a guanine or I'm sorry, appearing of guanine. So they always pair a pyre emitting with appearing. Now, if we take a look at the image over here on the right hand side, notice that it's focusing in on DNA base pairing and so DNA is made up of two strands on DSO. What you'll see is that there's one strand over here on the left and there is another strand over here on the right and these two strands, they connect to each other via, uh, interactions between the base pairs where once again a always pairs with t and C always pair with G. So notice that the A over here on this strand is always gonna pair with tease on this strand and vice versa. And the seas on this strand are always gonna pair with the GS on this strand over here and vice versa. And so once again, add means will always pair with findings and sido scenes will always pair with guanine. It's and so this is really important to note here. And so this year really concludes our introduction to the five nitrogenous bases and we'll be able to get some practice applying these concepts as we move forward. So I'll see you all in our next video