So now that we've covered loose connective tissues and some types of dense connective tissues, in this video, we're going to be putting it all together and briefly talking about what's under your skin. Now, it's important to note that later in our course in a different chapter when we're talking about the integumentary system, we'll talk a lot more details about the skin. But here in this video, we're only briefly going to talk about what's under your skin. And so there are actually many layers of connective tissue and epithelial tissue that come together to create the skin. And so notice down below we have a diagram showing you what's under our skin.

And notice on the left, we are focusing on the layers, whereas on the right, we have the functions for each of those layers. And so recall from our previous lesson videos that the outermost layers of our skin are made of epithelial tissue. And so notice that the outermost layer here, again, is made of epithelial tissue. More specifically, stratified squamous epithelium, which recall means that it's going to have multiple layers of these flat or squished cells on the apical surface. And the stratified squamous epithelium actually has multiple functions, but its primary function is protection.

It does protect, and it protects by preventing chemicals and microbes from penetrating through the skin into deeper tissues. Now, beneath the stratified squamous epithelium is areolar connective tissue, which recall is a type of loose connective tissue. And it is going to be highly vascular, meaning it has lots and lots of blood vessels, which is going to allow it to support the epithelial tissue which is avascular. Now, notice beneath the areolar connective tissue here in this darker blue region, we have the dense irregular connective tissue where the collagen fibers in the extracellular matrix take on an irregular or random fiber arrangement, which allows it to resist multidirectional forces, which is important for the skin to be able to do. And so notice that the dense irregular connective tissue here is making up a pretty large portion of the skin.

Now deeper to the dense irregular connective tissue is the subcutaneous layer, which contains adipose connective tissue. And adipose connective tissue has multiple functions including providing insulation, helping to keep the body warm. And so once again, later in our course, we'll talk a lot more details about the skin, but hopefully, this little diagram here putting it all together was helpful to show you how the skin comes together with these multiple layers of connective tissue and epithelial tissue. So, that concludes this video and I'll see you all in our next video.