In this video, we're going to talk about the second type of cartilage in our lesson which is fibrocartilage. And so, in terms of its characteristics, fibrocartilage is actually a little bit of a blend between hyaline cartilage and dense regular connective tissue which recall is a type of connective tissue proper. And also recall that connective tissue proper is sometimes referred to as fibrous connective tissue. And so the root fibro in fibrocartilage can remind you that fibrocartilage is a blend between fibrous connective tissue or connective tissue proper, mainly dense regular connective tissue, and a blend between cartilage or hyaline cartilage. Now, like all cartilages, fibrocartilage is avascular.

Meaning that it does not have any blood vessels. But unlike most cartilages in the body, fibrocartilage does not have a perichondrium or a layer of dense irregular connective tissue that surrounds the cartilage and usually has a blood supply that is able to support the avascular cartilage. But again, because fibrocartilage does not have a perichondrium, it does not have that supporting dense irregular connective tissue. And that means that fibrocartilage is going to rely even more on the diffusion of nutrients from surrounding tissues that may be vascular. And so, what that means is that fibrocartilage is going to have a tendency to heal slowly, very slowly.

And so, damages and injuries to fibrocartilage can really be detrimental to the health. Now, fibrocartilage is also going to be unique in that in addition to its chondroblasts and chondrocytes, it's also going to have some fibroblasts. Which recall, fibroblasts are cells of fibrous connective tissue or connective tissue proper. Again, another reminder that can be the root fibro in fibrocartilage, has some fibroblasts. Now, these fibroblasts recall, are going to be really important for producing the fibrous proteins in the extracellular matrix.

And in fact, fibrocartilage is known for having very very dense bundles of collagen fibers in the extracellular matrix. And because it has such dense bundles of collagen fibers, this actually makes fibrocartilage the strongest cartilage amongst the three different types of cartilage. And fibrocartilage, because it has so many dense bundles of collagen fibers, it's actually going to have relatively little ground substance in its extracellular matrix. Especially in comparison to hyaline cartilage. Now, in terms of its functions, again, because it has such dense bundles of collagen fibers, it's going to have quite a lot of strength.

And so, in terms of its function, it will be able to resist both compression forces that come with the bearing of weight from the body and it's also able to withstand tension forces from stretching as well. And so, in terms of body locations, we can expect to find fibrocartilage in areas of the body that need to be able to withstand lots of compression and tension. And so, they actually can be found making up the intervertebral discs, which is the fibrocartilage found in between the vertebrae of our spine. Which you can see over here in this image. Notice that we're zooming in on the spine of this woman here.

And notice that in between the vertebrae of the spine right here in blue is where the fibrocartilage can be found. And again, it's very very strong and so it can actually allow for shock absorption and cushioning. Now, it can also, fibrocartilage can also be found in the menisci of the knees. And the menisci is really just the meniscus of the knee. It's the plural version of the meniscus of the knee.

And so, in the knee, of course, that's in the lower part of our body. And it needs to be able to withstand lots of compression forces, since it's bearing the weight of our entire upper body, pretty much. And so, it's really important to have really really strong fibrocartilage in the menisci of the knee. And so notice down here we have a micrograph showing you some fibrocartilage and what you'll notice is that again, we're highlighting the chondrocytes within the lacunae, which again are those chambers that house the chondrocytes. There are also going to be chondroblasts and some fibroblasts in fibrous connect cartilage as well.

Fibrous cartilage has some fibroblasts. And the extracellular matrix, which you'll notice has really, really dense bundles of collagen fibers that are more regularly arranged, which is why it's more of a blend between dense regular connective tissue and not so much dense irregular connective tissue since the bundles of fibers are not totally randomly arranged in fibrocartilage. And so, this here concludes our lesson on fibrocartilage and moving forward, we'll be able to apply these concepts and talk about the last type of cartilage in our lesson as well. So, I'll see you all in our next video.