In this video, we're going to talk about the second type of simple epithelial tissues which is simple cuboidal epithelium. And so we already know that the term simple indicates that this tissue has just one single layer of cells. And so recall that the term cuboidal indicates that the cell shape is going to be cube-like or box-like. And so we can say that simple cuboidal epithelium is going to consist of just one single layer of these cube-shaped cells or box-shaped cells just like what we see over here in our diagram. And so notice that we have just one single layer of cells where all of the cells come into direct contact with the underlying basement membrane.

Again, this is the defining feature that makes it one single layer of cells. And notice that the cell shape is box-like or cube-like. Now in comparison to simple squamous epithelium that we covered in our last lesson video, simple cuboidal epithelium is going to have significantly more cytoplasm. Because again, the simple squamous cells from our last lesson video are squished cells that are flat. And because they're so flat, they don't have much cytoplasm, and that leaves very little room for organelles.

But with these cuboidal cells, they are more box-shaped, and so they have more volume and more spacious cytoplasm, and that makes more space for organelles. And so, those organelles are going to be important for the functions of simple cuboidal epithelium, which are for absorption and secretion. And so, absorption again indicates the uptake of nutrients, and secretion refers to the release of products. And so, this is also going to help with the locations that simple cuboidal epithelium can be found. And so, because again, it's associated with secretion and absorption, it's going to be important for areas such as the kidney, and it forms the tubules of the kidney, which are important for filtration.

Again, absorbing substances and excreting other substances. And also, it's going to be important for secretion as well. And so we know that it can be making up the ducts of many different glands. For example, simple cuboidal epithelium makes up the ducts of salivary glands and mammary glands. And it also forms the secreting portions of the thyroid gland.

And it makes up the ducts of the pancreas as well, which is another type of gland. And so, down below what we have is an ID tip to help you identify this tissue under a microscope. And so, usually, the micrograph that's going to be shown is going to show the simple cuboidal epithelium as part of a duct or a tubule. And so what this means is that the simple cuboidal epithelial cells will usually be in a ring shape. Or if they're not in a ring shape, they're going to have an open space between the two layers of cuboidal cells.

And so notice up above here, we're showing you an image of one of the kidneys. And here, what we're showing you is a micrograph. And notice that the micrograph here is a little bit difficult to see, but when we draw a sketch of the same micrograph, it makes it much easier to see the simple cuboidal epithelial tissue cells. And so notice that these simple cuboidal epithelial tissue cells are forming a ring here because they're forming the tubules of the kidney. And again, those tubules are going to form a, basically a tube.

And so notice here that we have this ring of simple cuboidal epithelial tissue cells, and you can see the open space here, which is also referred to as the lumen of the tubule. And notice that the surrounding tissue here is most likely going to be connective tissue. Now, what you'll notice is that because these simple cuboidal epithelial tissues form tubules and ducts, they are going to resemble the structure of a hose, if you will, a water hose. And so just like you can see the simple cuboidal epithelial tissue forming a ring here, you can think that that's just the ring of the hose. And if you continuously stack and layer these simple cuboidal epithelial tissue rings, you can form a hose.

Which is going to allow for the transport of liquids, just like a hose allows for the transport of liquids. And again, this is how liquid products can be secreted into these ducts and tubules and things of that nature. And so this here concludes our brief lesson on simple cuboidal epithelial tissue, 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.