When it comes to fatty acids, we're gonna say that most fatty acids contain an even number of carbons, typically 12 to 26 with a generic or general formula of CH three ch two N coo HN can vary based on the length of the fatty acid chain. Now, we're gonna say also that fatty acids are amp paic molecules, meaning they have both nonpolar and polar parts. We're gonna say that this depiction, this image on the right represents a fatty acid. The fatty acid itself has a hydrophobic tail. And that's because the tail is made up of only hydrocarbons, only carbons and hydrogens making it nonpolar and because it's nonpolar, it's hydrophobic, we're gonna say the carbolic acid has a hydrophilic head. Hydrophilic means water loving. And why is that? Because the carbolic acid head is polar. If we take a look here at this image based on the length of the fatty acid chain, we're gonna say this represents uric acid. Remember that the hydrocarbon tail would be hydrophobic and then the carbolic acid head would be hydrophilic. We say that typically our fatty acids are between 12 and 26 carbons, only one of these carbons is part of a polar a part, the rest of the tail is nonpolar. So we're gonna say here, the larger the hydrocarbon tail then the more nonpolar the fatty acid. Therefore, overall fatty acids are nonpolar. So just remember when looking at a fatty acid, we have two parts to it. The hydrophobic hydrocarbon tail and the hydrophilic carbolic acid head.
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example
Fatty Acids Example 1
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Which of the following statements about fatty acid structure is correct. A carbolic acid group of the fatty acid is polar. Well, that's true. It's hydrophilic and does not interact with aqueous environments. This part is false because the head is polar. It should react with aqueous environments, meaning water fatty acids contain a nonpolar head with a polar tail. Now, here's the opposite. They have a polar head and a nonpolar tail. Fatty acids are amphoteric. So remember, amphoteric means that it can exist as an acid or base. It's not amphoteric. It's amphipathic, meaning it has a polar and a nonpolar section. Fatty asses consist of a hydrophilic head. True and a hydrophobic tail. That's also true. So here, the only statement that's correct would be option D.
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Problem
Problem
Which of the following fatty acids would you expect to be more soluble in cyclohexane?
A
Palmitic acid (16 Cs)
B
Stearic acid (18 Cs)
C
Lauric acid (12 Cs)
D
none of the above
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concept
Fatty Acids Concept 2
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So in this video, we're gonna learn the distinction between a saturated versus an unsaturated fatty acid. Now, when we say saturated, these are the fatty acids that contain only carbons single bonded to carbons. When we say unsaturated, we say these are the fatty acids containing at least one carbon double bonded to a carbon. So again, saturated, they're all single bonded to one another in a unsaturated there, there's at least two carbons double bonded to each other. Now mono and poly prefixes indicate one and multiple double bonds respectively, mono meaning one poly, meaning many, we're gonna say here, naturally occurring fatty acids contain what we call cysts double bonds. Remember sis means same side. This is different from trans, which means opposite side. If we take a look here, we have a saturated fatty acid in the form of uric acid. Here. It's this portion that we're looking at in terms of saturation is just a bunch of carbon sign body to each other. And that's why it is a saturated fatty acid below it, we have OIC acid and Leno acid, oh le linoleic acid, linoleic acid. And we're gonna say here that if we look OIC acid has one double bond, one pi bond. So it's mono unsaturated fatty acid. And we're gonna say here that linoleic acid, it has two double bonds. So it would be polly unsaturated. Also, remember if we look at the double bond, we would say that this bond points down, this bond points down, they're on the same side pointing the same direction. That's why its same with this one. Your goals are double bond here, double bond here and the bonds coming off are pointing in the same direction down. These would be two cy bonds. OK? So that's what we mean by cis in nature, right? So remember when we say saturated, that means that the hydrocarbon tail, the nonpolar portion has no double bonds. It's all single bonded carbons to one another. If it is unsaturated, there's at least one double bond somewhere on this hydrocarbon tail uh where two carbons are double bonded to each other, right? So just keep that in mind.
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example
Fatty Acids Example 2
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In this example, it says classify each fatty acid as saturated with an S mono saturated with mono or poly unsaturated with poly. So in the first one, we can definitely say that this is an unsaturated fatty acid because of the presence of our double bonds or pie bonds. We would say that there are 1234 of these double bonds or pie bonds. That will mean that this is a poly unsaturated fatty acid for the next one, same thing. Again, we have 123 double bonds. This time again, these are sites of saturation. Since there's more than one, this would be a poly unsaturated fatty acid. And then finally, for the last one, we look at the hydrocarbon tail, there are no double bonds that we can see no pie bonds. Therefore, this would be a saturated fatty acid. OK. So here we just put s so this is how we classify each of the three fatty acids that we see within the given example. Question.
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concept
Fatty Acids Concept 3
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In this video, we're gonna take a look at omega fatty acids. Now, remember we have alpha, which means beginning omega, which means the end. So Omega must have something to do with our end of our fatty acid chain. Now, here we're gonna say unsaturated fatty acids can be classified by the first double bond numbering from our methyl carbon. The methyl carbon is the end carbon of my fatty acid chain. And therefore, it represents my omega carbon. If we take a look here, it says we have an omega three fatty acid, that means the first double bond is located at the third carbon. If this is this is our metal group right here. So this is our omega, our omega carbon. We're gonna say we count 123 to get to the, to the double bond. So carbon number three is where we get to our double bond. That's why this is an omega three fatty acid in omega six fatty acid, the first double bonded double bond carbon is located at the sixth position. So sixth carbon. Here we're going to say here is our omega again, this metal group right here and just count to see how long it takes you to get to the double bond. We go one, 234, 56. We had to count to six to get to that double bond. That's why this is an omega six fatty acid. So again, just remember when we talk about omega fatty acids, it can be omega three or omega six. And here we look at the methyl group, the end of the fatty acid chain and count to see how far it takes us, how long it takes us to get to the double bond. Does it take us to the count of three? Making it an omega three fatty acid? Or do we have to count to six to make it an omega six fatty acid?
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example
Fatty Acids Example 3
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In this example, it says label the following unsaturated fatty acids based on Omega classification. So with omega, we're looking at the methyl group in each one and all we have to do is count to see how long it takes us to get to the double bond. So for a, we go 1234 56, we had to get to the sixth carbon to get to our double bond making this in omega six fatty acid. For the next one. Let's count here's one, 23456789. In this one, we have a new type of omega that we haven't seen yet. This is an Omega nine fatty acid, but the process is still the same. The omega carbon is the methyl carbon, the carbon at the end count from the omega carbon to the double bond, seeing how long it takes to get there. What carbon do we land on that tells us the type of omega classification. So for option A, we have an Omega six fatty acid. And then for me, for option B, we have an Omega nine fatty acid
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concept
Fatty Acids Concept 4
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In this video, we're gonna take a look at fatty acid shorthand notations. Now we're gonna say fatty acids are assigned shorthand notations for easy naming. Now here this is based on the number of carbons followed by the number of double bonds separated by a colon. If we take a look at the top fatty acid in blue, this would be the number of carbons total for the fatty acid. Remember this is a carbon part of the carbolic acid group. So we go 123456789, 1011, 12, we have 12 total carbon. So this will be 12 and then we have a colon, we have no double bonds at all. So this would be zero. So the shorthand notation for this fat ass will be 12 colon zero for the next one. The total number of carbons is what 12345678, 9, 10, 1112, 1314, 1516, total carbon. So this will be 16 and then we have one double bond involved. So this would be colon one. So this would be 16 colon one as the shorthand notation for this particular unsaturated fatty acid.
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example
Fatty Acids Example 4
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Here in this example, it says provide a shorthand notation for the following fatty acid below. All right. So remember our shorthand notation for fatty acid is based on one, the number of carbons the fatty acid possesses followed by a colon and then the number of double bonds the fatty acid possesses. So if we take a look here, we're gonna see how many carbons does this possess? It possesses 12345678, 9, 1011, 1213, 14, 1516, 1718 total carbons. So we'd have 18 Holland and then followed by the number of double bonds that it possesses, it possesses 12. Remember it's carbon carbon double bonds that it possesses, it possesses two of them. So this would be two. So the shorthand notation of this particular unsaturated fatty acid would be 18, followed by Colin, followed by the number two, right? So this would be our final answer.
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concept
Fatty Acids Concept 5
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When it comes to remembering fatty acids, we're gonna say that to be able to draw more complex lipids. We first need to memorize structures of the common fatty acids. And we're gonna say here that we have a list of some common fatty acids from 12 carbons all the way up to 20. So we have 1214, 1618 and 20. We have Loic acid, we have Myristic acid, we have pic acid, sic acid and Eric acid. Now, how exactly will I remember these different types of common uh fatty acids? Well, first remember we're starting out with the number 12, we're going up two at a time till we get to 20. These are our common types of saturated fatty acids. None of them have py bonds. And what we can do here is our memory tool. Number one, this will help us to remember the order of these different types of common saturated fatty acids. And here the memory tool is that Laurie Mystic Palace stores. Art here looking at the first letter of this memory tool will help us to remember the names of these different types of saturated fatty acids, right? So Laurie is Loic acid. Mystic we're gonna say is Myristic Acid Palace is pit acid stores, is ster acid and then art is Eric uh Eric acid, right? So just keep this memory tool in mind when we're trying to remember the common types of fatty acids starting out with 12 carbons all the way up to 20.
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example
Fatty Acids Example 5
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In this example question, it says without looking at the table above, identify the number of carbons present in each saturated fatty acid. So remember our memory tool, one says that lorries, Mystic Palace stores art. So here LM PS and A and when it comes to these common fatty acids, we say they start out with 12 carbons and they go to 20. So we have 12 carbons for lorries, then 14 for Mystic 1618 and then 20. Here. The first letter in this memory tool is connected to the first letter of these different types of fatty acids. So Laurie's is with loic acid which has 12 carbons. We already know that after this is 12 coal and zero because it has no double bonds. We don't care about the number of double bonds. We want the number of total carbons. Next uh Mystic M here Myristic. So this is 14 Palace is palmitic. So that's 16 S is for STAIC that'd be 18 and then 20 acidic acid A art. So this is the number of total carbons we have for each of these saturated fatty acids based on our memory tool. One. So remember keep it around. Remember it to help you start out figuring out how many carbons and double bonds we have for each one of these saturated fatty acids.
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Problem
Problem
Provide a condensed structural formula for a fatty acid with 18 carbons (18:0) and give its common name.
A
Storic acid
B
Palmitic acid
C
Stearic acid
D
Palmitoleic acid
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concept
Fatty Acids Concept 6
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In this video, we'll take a look at some of the most common types of unsaturated fatty acids and memorize them using our memory tool. Number two. So here our memory tool number two says that 16 Palms occupy lovely lush, 20 acres. So 16 Palms, our first unsaturated fatty acid here has 16 carbons and it has one double bond. So here this is Palmetto Lake acid and then here we have OIC acid here, this would be 18. We see it has only one double bond. Next, we have linoleic acid which is still 18 carbons but two Pyon. So two, then we have linoleic acid. These two are so close together. All right. So here we're gonna have 18 and then three. Next, we have Arachidonic acid, which is 20 because of 20 acres. And then we see that it has four double bonds. So this is four. Now a couple things to note in terms of these double bonds, the ones in purple, the first four, the double bonds start at carbon nine from the carbonel group, right? So we count to see how far they are to see where it starts, right? So if we locked any of them. 123456789, they all start nine carbons on carbon number nine. Now, here for Arachidonic acid, it's the fifth acid and the double one starts at carbon number five from the carbon carbon, right? So we have 1234 and five carbon, five fifth carbon in this group of common unsaturated fatty acids. All right. So just remember utilize memory tool two to help you memorize some of these common unsaturated fatty acids.
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example
Fatty Acids Example 6
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For this example, it says provide shorthand notations for each fatty acid. These here represent our unsaturated fatty acids. Our memory tool number two tells us that 16 palms occupy lovely lush, 20 acres. So here, if we take a look, we have P we have OL and L and A. All right. So if we take a look here for palms, we're dealing with uh palmetto Laic acid. This would be 16 1. Here we have occupy which is OIC acid. We go up by two and stay the same in terms of number of pi bonds. So still one and then here these three here are, are 18 carbons and the number of pi bonds increases. So 18 1, then 18 2, then 18 3. This is a le linoleic leola acid. This is linoleic acid and then we have 20 acres, which is Arachidonic acid. Here we go up by two again. So 20 then it goes up one more Pyon to four. All right. So we can see that we have 16. Then these three stay 18 and it's the number of pi bonds that's increasing. Then we go up to 20 here and still the number of pythons increases by just one more to 24. All right. So here, if we take a look, uh linoleic acid is lovely. So this would be 18 2 occupy is lic acid. So this would be 18 1. Ar Ar Aon acid is 20 acres or 20 and then four and then linoleic acid is lush. So that's 18 3. So this would be the shorthand notation for each of these unsaturated fatty acids.