In this video, we're going to briefly discuss carbohydrate functions. It's important to note that carbohydrates can actually be very structurally and functionally diverse, meaning that they can have many different types of structures and many different types of functions. However, for the purposes of our course, we're going to focus on 2 main functions that you should be aware of.
The first main function of carbohydrates that you should be aware of is structural support, so some carbohydrates are going to be used to build structures. For example, cellulose is a Polysaccharide that is used as structural support in plants. Thus, cellulose is used to build plant cell walls. Chitin is another example of a structural support polysaccharide that's used in animals such as insects and crustaceans. There are other examples of structural support polysaccharides such as peptidoglycan, which is used to build the cell walls of bacteria.
Now, the second main function that you should be aware of that carbohydrates tend to have is energy storage. There are some polysaccharides that are going to be used primarily for short-term energy storage. For example, the polysaccharide starch is used as energy storage in plants and the polysaccharide Glycogen is used for energy storage in animals.
If we take a look at our image down below, we'll be able to summarize some examples of these polysaccharides and their functions in plants and animals. You'll notice that in this column, we have the function of the polysaccharide, then in this column, we have the polysaccharides that are found in plants and in this column, we have the polysaccharides found in animals. When it comes to the function, there are two primary functions that you should be aware of: structural support, which is used to build things just like this house here is being built, and energy storage just like these batteries here store energy.
When it comes to polysaccharides in plants, an example of structural support polysaccharide in plants is Cellulose. Cellulose is going to be the most abundant carbohydrate and it is going to be found in plant cell walls. Notice that here we have a leaf and we're zooming into the cell walls of the cells that make up that leaf, you'll find cellulose. Here we have an image that represents cellulose, again a polysaccharide, a carbohydrate for structural support making the cell wall.
For animals, a polysaccharide that is involved with structural support is again going to be chitin. Chitin is going to be found in the exoskeletons of insects and crustaceans such as lobsters, for example, and so the hard shells that make up the lobsters here when you zoom into them you'll find the polysaccharide chitin.
When it comes to energy storage in plants, a classic example is going to be starch. When you think of starch you might think of potatoes, for example. So here we have a potato, and potatoes are going to have lots and lots of starch. Here we have an image that represents starch and again starch is a storage polysaccharide, which stores, glucose specifically in plants. And so, plants will store their glucose as starch.
On the right over here, what we have is an animal liver, and the animals will use the polysaccharide Glycogen as an energy storage polysaccharide. Notice here within the liver we have this molecule here which represents the glycogen polysaccharide and it is a storage form of glucose specifically in animals. Once again here, carbohydrates can have many different types of functions, but mainly structural support and energy storage.
Notice that plants and animals have these characteristic polysaccharides that are found in each of them with specific functions. This here concludes our brief lesson on carbohydrate functions 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.