In this video, we're going to introduce fatty acids. And so fatty acids are defined as hydrocarbon chains of varying length with a carboxylic acid functional group at the very end. And so we'll be able to see some examples of fatty acids down below when we get to our image. Now really there are 2 main types of fatty acids that you all should know. And the first main type are the saturated fatty acids, which as their name implies with the saturated, these are fully saturated with hydrogen atoms.
And so this is because they only contain carbon to carbon single bonds. And when they contain only carbon to carbon single bonds, that means that they can be fully saturated with hydrogens. Now, saturated fatty acids tend to be solids at room temperature. And so let's take a look at our example down below at the saturated fatty acids, which we have over here on the far left-hand side. So these are saturated fatty acids, because notice that the hydrocarbon chain that we have here, which is only made up of hydrogens and carbon atoms, they're fully saturated with hydrogens.
They have the maximum amount of hydrogens on them because notice that the carbon-carbon bonds in here only contain single bonds as we mentioned up above. And so, notice that, this hydrocarbon chain here at the very end, it has a carboxylic acid group, which was right here. It's basically a carboxyl group. And so that is why this is a fatty acid, and it's saturated once again because the hydrocarbon chain is fully saturated with hydrogens. Now notice that over here, this is another way to represent the hydrocarbon chain where each of these corners that you see here, each of these points represents a carbon atom, and notice that the hydrogen atoms aren't being shown.
It's just another representation, of the same exact molecule. That's why we have the equal sign in between them. Now once again, saturated fatty acids, they tend to be solids at room temperature just like this butter up here. Butter, is of course solid at room temperature, and so that is a source of saturated fatty acids. Now the second main type of fatty acids that you all should know are the unsaturated fatty acids.
And so the unsaturated fatty acids, as their name implies, are not fully saturated with hydrogens. And the reason that they're not fully saturated with hydrogens is because they have the presence of at least 1 carbon to carbon double bond. And so the double bonds that are in the hydrocarbon chain, they create a bend in the chain or a kink in the chain. And the kink in the chain ultimately makes these unsaturated fatty acids liquids at room temperature instead of being solids at room temperature. And so when we take a look at our image down below over here in the middle, notice what we're showing you is an example of unsaturated fatty acids.
And notice that the hydrocarbon chain that we have here is not fully saturated with hydrogens because there is a carbon to carbon double bond, and so they are missing some hydrogens here at these positions. And so that's why they call them unsaturated because they're not fully saturated due to the presence of a double bond. Now notice that the double bond also creates a bend in the chain. It's not straight or linear like the saturated fatty acids are. It creates a bend or a kink in the chain.
And so because it has a kink in the chain, the unsaturated fatty acids, they cannot be tightly packed together, so they're going to remain relatively loose. And that loose nature is why they are liquids at room temperature. So these oils, vegetable oils, and olive oil and things like that, they are examples of unsaturated fatty acids that are liquids at room temperature. Now there is one subset of unsaturated fatty acids that are called trans fatty acids. And so you may have heard of trans fatty acids or trans fats before, and really these are a subtype of unsaturated fatty acids.
That's why we have them grouped in the same grouping as unsaturated fatty acids. So trans fats are artificial unsaturated fatty acids. And instead of having a kink, the trans fats, they actually do not have a kink in their chain. So they have a double bond, but the double bond does not make them kinked, and so they remain linear. So let's take a look at the trans fatty acid, which we have down below right here.
And so notice that the trans fatty acid does have a double bond in its chain. However, notice that the double bond that's in the chain of the trans fatty acid does not create a kink in the chain or a bend in the chain like other unsaturated fatty acids. Trans fatty acids specifically are going to have straight chains despite having a double bond in them. Now trans fatty acids, again, they are artificially made, and so you'll find them in foods like burgers and French fries and things of that nature. And so that's why we have this image right here.
And trans fatty acids usually they're associated with being very unhealthy. And so this is typically types of foods that you would want to try to avoid in your typical everyday diet. And so this here concludes our introduction to fatty acids and the difference between saturated and unsaturated fatty acids. And we'll be able to get some practice moving forward in our course. So I'll see you all in our next video.