 So, our next tissue to think about is called stratified squamous epithelium. Stratified squamous epithelium is the first tissue that we've looked at that is actually stratified, meaning that it has layers of cells. Now, because this tissue has layers of cells, its number one job is protection. And so, simple or excuse me, stratified squamous epithelium is found in places such as your skin. Your skin is an organ of the integumentary system, but part of the skin is something called the cutaneous membrane. The cutaneous membrane is what contains this stratified squamous epithelium. So we have a micrograph of the tissue over here, and this is just what's called a thin skin slide. It's thin as opposed to thick like you might have on your heel, for example. And if we look at stratified squamous epithelium, we can see that we have several layers of cells. You can see a nucleus here and here and here and here and here. All of these are nuclei, and of course that is representing a place where a cell is found. So we have many layers of cells in this particular tissue. But one thing that is important to notice, and you can see it particularly in this area, is that the cells tend to flatten out as they move up. Now you'll learn about this more when you study the integumentary system, but this first layer of cells, which are sort of cube shaped cells, this layer of cells is the one that undergoes cell division. So one of those cells will divide and make two. And when they do that, the older cell moves up into the next layer, so to speak. And then as the cell division occurs again down here, then the cell moves up again and moves up again and moves up again. But as the cell moves up, it also indicates that the cell is getting older. And in your skin, as the cells get older, they take on a protein called keratin. And as they take on this keratin, the cells flatten more and more, and by the time they get up in this area, many of them have lost their nucleus. And if you look in this area, you can see cells that are no longer living. But that layer of dead cells really helps afford you even more protection before you get to the living cells. So stratified squamous epithelium, its job includes protection mainly. It's made up of many layers of cells, and we find this, for example, in the skin.