Simple means one layer, and that's usually the for that diffusion. D be a perfect cell for iffusions. But then you can stack them on top of each other, like the lage box,. You can put squamus on top of squamus in epidermis skin. Ik, craning a brick wall, like a brick wall. And that's going to be not so good for diffusion, but good for protection. It makes total sense. Things will easily get through that. So it's there for eros of abrasion, like an epidermisand to add to that portion of c we could use in that protection layer. What are some other examples of