In anatomy, a serous (or serous membrane) is an epithelial membrane composed of a thin layer of epithelial cells and another thin layer of connective tissue. The serous ones cover the body cavities and cover the organs that are in them, besides secreting an aqueous fluid that reduces the friction and acts as lubricant in the friction between the different elements of that cavity. They differ from adventitious membranes where the function of the latter is to maintain the location of organs rather than to reduce friction, which is the function of the serous (eg, retroperitoneum).
Each serosa is composed of a secretory epithelial layer and a layer of underlying connective tissue.
You can talk about two types of serous membranes, although in reality it is the same membrane with different name depending on the position it occupies. Thus, the serosa that covers a cavity similar to the painting that covers the walls of a room, is called parietal serosa. While the serosa that upholstery the organs that are in that cavity, denominates visceral serous.
There are some organs whose serosa receives a specific name, usually due to the importance of its function. These are:
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