So now that we've covered connective tissue proper, including loose and dense connective tissues, in our previous lesson videos, in this video we're going to begin our lesson on the second major class of connective tissues, which are the specialized connective tissues with a focus on cartilage for the next few videos. Recall from our previous lesson videos that specialized connective tissues, as their name implies with the term specialized, are going to be optimized for very specific roles that are unique to the tissue. This is different than connective tissue proper, which tends to have more generalized functions and roles. Also, recall that specialized connective tissues tend to have a ground substance in the extracellular matrix that is either a solid or a liquid, rather than being a gelatinous semi-fluid like the ground substance of connective tissue proper. Recall from our previous lesson videos that there are three different types of specialized connective tissue: cartilage, bone, and blood and lymph.

Moving forward in our course in separate videos, we're going to talk more about each of these three different types of specialized connective tissue. Notice down below, we have our map of the lesson on connective tissue. We know that connective tissues can be grouped into two major classes. The first major class is connective tissue proper, or general or fibrous connective tissues, which includes loose connective tissues such as areolar, reticular, and adipose tissues, and dense connective tissues such as dense regular, dense irregular, and elastic connective tissues. We've already covered connective tissue proper in our previous lesson videos, and so here in this video, we're focusing our attention on the second major class of connective tissues, which are the specialized connective tissues, which once again includes cartilage, bones, and blood and lymph.

Now, what you'll notice is that there are three different types of cartilage, including hyaline cartilage, fibrocartilage, and elastic cartilage. Moving forward in our course, we're going to talk about all of these different types of specialized connective tissues in their own separate videos in more detail, starting with cartilage. This concludes our introduction to our lesson on specialized connective tissue, and I'll see you all in our next video to learn more about cartilage.