Nitrogenous Bases - Video Tutorials & Practice Problems
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Nitrogenous Bases Concept 1
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Hey, everyone. So when it comes to nitrogenous spaces, we're gonna say there are five different nitrogenous spaces that are grouped into two categories. We're gonna have our pyrimidines versus our purines. Now, pyrimidines, these are our single ringed molecules and our purines are our double ringed molecules. Now, here we have memory tools to help us remember which is which when it comes to our pyrimidines, we're gonna have our cytosine, our thymine and our Ell. When it comes to thymine, this is only found within DNA and ELL is only found within RN A. Later on, we'll talk about their given structures right now. We're only caring about grouping them. So these three nitrogen spaces all are single uh molecules, single ringed molecules. And our memory tool here is that creepy tombs under pyramids, pyramids remedy. Creepy for cytosine tombs for thymine and under for uracil. Here there are one letter radiations would be CTU. On the other side, we have our purines which are our adenine and guanine. So A and G. So it's two rings fused together when it comes to these structures. And our memory tool here is pure as gold pure for purines as for Adenine and then G Gold gui, right? So just remember we have our creepy tombs under pyramids and purest gold to help us group our five nitrogenous bases into their two categories being either single ringed molecules or double ringed molecules.
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example
Nitrogenous Bases Example 1
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So in this example, it says label each nitrogen space as a perimeter py or a purine. Pu So remember when it comes to our pets, we're gonna say here, creepy tombs under pyramids. So here if we, these represent our pyrimidines, when we say creepy here, creepy here stands for cytosine. So this will be py tombs is for thymine. So py you here under is your cell. So py and then for purines, we're gonna say purines are pure as gold. So our purines pure as is for Adenine or a A nine. So here this would be pu and then gold G here is for Gui. So this is how we label each of the following nitrogenous bases. Based on these two memory tools, we can group them into pyramids or purines.
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Problem
Problem
The four nitrogenous bases commonly found in DNA are:
A
Uracil, cytosine, guanine, thymine.
B
Adenine, thymine, cytosine, uracil.
C
Uracil, adenine, cytosine, guanine.
D
Adenine, thymine, cytosine, guanine.
E
None are correct.
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concept
Nitrogenous Bases Concept 2
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In this video, we'll learn some tricks to help us remember the structures of different perimeters. So here, first of all, when we say a perimeter, this is the general structure of perming the three perimeters that we have are just modifications to this original structure. And it all begins with Uracil Uracil. Here has its two nitrogens just like Peridin does, but it also has two carbon groups. So we have a double bond O here and a double bond O here. Now, here we had a double bond, but we can no longer have a double bond here because then this carbo was making five bonds. So that's not allowed. But nitrogen ideally wants to make fi um three bonds to do that. It would have to be connected to a hydrogen. So it would have a connection to the two carbons. And then the third bottle would be to the hydrogen. We run the same issue here with this bottom nitrogen. We can't have a double bond like we have here because in this carbon, carbon will be making five bonds, carbon can only go up to four. So for nitrogen to reach its three bonds, its ideal number of bonds, it'd be connected to a hydrogen. So this represents the structure of your cell. So just remember, we have our two carbons here and then each of the nitrogens to make their third bond connects to a hydrogen. Now, here you, so the other two hermits are just modifications of this thyme, thyme, methyl. So thythy, this is telling me that uracil and thymine are very similar in structure. The only difference is that there's a metal group involved, the metal group would be right here and then we still have our two carbon eels here and here and there are nitrogens would still have an age of peace. So this is tiny. Now, cyto is a little bit trickier but just remember, we're gonna say cytose Issy a main group. All right. So when we see mean group, kind of have a moment of like, oh gosh, here it goes, sigh a mean group. So what does this mean? Well, we're gonna still have our carbonel here. We're gonna still have an H on this nitrogen here. But now we're still gonna possess this double bond just like this nitrogen here possesses a double bond. It's making its three bonds. So it doesn't need an H on it. And then Sai Amin Amin, right? It's pronounced the same way as an amine, the functional group am mean, which we know is an H two group. So instead of having two carbons, we have one carbonel and one NH two group right here. So this represent our cytosine. So just remember this is the starting structure of pid. The three pyrimidines are just modifications of it. It all starts with your cell. And from there, from ell, you can adapt it to give us thymine or to give us cytosine. This is the key to remembering the structures of these different types of nitrogenous spaces.
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example
Nitrogenous Bases Example 2
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Here is this example question. It says complete a structure of thymine base. So remember to draw thymine, we need to remember the structure for Ell, if we can remember the structure for Euros, we just adapt it to give us thymine. Now, first of all, remember that our pets have this basic structure involved. We have our nitrogens here. This will make a double bond, double bond here and double bond here. This is the general structure of a perm your cell. All we do now is we adapt this structure. We have two carbonel groups here and here we still have our double bond here. The nitrogen still need to make three bonds and they do that by adding an H to each one. This would be your thymine. We can get thymine. Just remember methyl because it's connected to thymine. So here with that, it just means we have this similar structure. The difference now is we're gonna add a methyl group. So we still have a double bond here. We'd have our two carbon. Still, each nitrogen would still have an H methyl or thymine. The metal will come off of this carbon here. So this will represent the structure for thyme. Remember we were able to do it by first remembering what a pyrimidine looks like in terms of this structure. Then remembering modifying this structure to your cell. And then just remember if you know your cell thymine is almost the same except we have a methyl involved. So add the methyl group to the appropriate carbon and there you have it. Thymine represents what we have within the box.
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Nitrogenous Bases Concept 3
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In this video, we'll talk about some tricks that we could remember in order to draw purine structures. Now, a purine, the base form is this, we have two rings fused together and we see that we have four nitrogens within, embedded within those rings. Now, adenine, remember the structure of Adenine. Just remember Adenine add a mean and a mean is an NH two group. Here, we're just gonna add an NH two group to the structure. So here we still have a double bond on this nitrogen and we would add our mean to this carbon right here, our NH two group and this will represent atomy. Now guanine to remember the structure of guanine, we're gonna say go first, this red oxygen indicates that we have a carbon and there goes our red oxygen now because we have that carbon carbon there, it cannot make a double bond, otherwise it making five bonds, right? So a double bond cannot go here. That means this nitrogen is only making two bonds. Ideally, it wants to make three to get that third bond, it has to connect to a hydrogen. So waning, we have to go part and then the second part is a mean. So again, we have a mean involved and Amin is an NH two group, that NH two group would go right here. So this represents our structures of adenine and guanine. But again, it all originates from the base form of purine, which is our two fused rings with four nitrogen atoms embedded within them.
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example
Nitrogenous Bases Example 3
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Here it says complete a structure of the guanine base. So remember guanine, which is a purine is and its base form of purine would be these two nitrogens having double bonds. But we're gonna adapt this base form of purine to give us guanine at the end. Now, to remember the structure of Guan, we just have to remember, go a me. So to go that red oxygen indicates we have a carbon neal group, we have to get rid of that double bond there because if we didn't that carbon carbon, we making five bonds, carbon can only make up to four bonds. Now, this gives us an issue though this nitrogen now isn't making three bonds like it ideally wants to, it's only making two. So in order to make that third bond, you'd have to gain an H. Next we have Amin. Remember an Amin is an NH two group, that means we'd have to add an NH two group somewhere to the structure, which would be right here. So here this will represent the structure of our guanine nitrogenous space. Remember we've just adapted the base form of our purine molecule in order to get this particular nitrogenous space.
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Problem
Problem
Select a correct structure for U.
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Problem
Problem
Draw a structure for cytosine.
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