Now, the next portion we're going to discuss is our epithesis. And the epithesis contains a special type of bone structure known as our spongy bone, also known as the cancellus bone, as well as our trabicular bone. And it's called trabicular because the structure resembles a honeycomb, it resembles a sponge. Now, inside the spongy bone, which is not dense, by the way, so that means it's relatively light and flexible. Inside the spongy bone, we have a specialized region known as the red bone marrow. And the red bone marrow is where we basically produce our red blood cells as well as our white blood cells.