 Today we're going to talk about the membranes in your body and specifically we're going to talk about serous membranes today. Serious membranes surround the organs of the body. So imagine if you didn't have some kind of protective membrane around the organs and that heart specifically would be pumping thousands and thousands of times. Okay, next to those other organs and tissues nearby. Just like my fist is moving in my hand, you can really start to feel that friction building up in there and that heat and you can imagine some damage that it might do to those fragile organs. So serous membranes then surround the organs and allow for that space and those a cavity literally around those organs to help reduce the friction. So serous membranes, we have two serous membranes around each of our organs. Just like this bag has two sides to it. So we have an outside and an inside part of the, we have a two sides to it, an outer part and an inner part of this. If we put our pseudo organ into our pericardial membrane here, notice too that between the two membranes, I've added some fluid. So some thin fluid just like serous fluid is thin fluid inside of these two membranes. So if these are surrounding the organ, like so, you can tell that there would be an inner membrane and then the outer membrane and then you can see the serous fluid between the two on the inside. So as that organ is moving, for instance, the heart pumping between those two membranes, then that fluid between those two will help reduce that friction and literally protect that organ. So these two membranes, these two again are called serous membranes and there's two of them. You see my heart here on the picture and you see this inner membrane here. That inner membrane is going to be called the visceral membrane. So in this case, it'll be visceral pericardium. The term visceral means organ and so any of our membranes that are around our organs in the body will have that term visceral, visceral membranes, visceral pericardium in this case. Then you see the outer membrane around here and that covers the wall of the entire organ and area. So we call that one the parietal membrane. Pariet means wall. Parietal pericardium in this case then. So the parietal membrane is on the outside, the visceral membrane is on the inside, and then notice in between then there's that thin serous fluid. So the serous fluid is inside the cavity. So the pericardial cavity is between these two serous membranes. The fluid in between is then the serous fluid. Again, a thin fluid that as you can see will help reduce the friction as that organ moves. Those are your serous membranes.