In this video we're going to go over the types of
body membranes, their structures, and the different areas in the body that they're located. Body
membranes are comprised of epithelial tissue and connective tissue, and there are four
types found in the body, mucous membranes, serous membranes, synovial membranes, and the
cutaneous membrane. Let's start by looking at the cutaneous membrane, which is also known
as the skin. It is composed of a top layer of epithelium and a bottom layer of connective
tissue. The top epithelial layer is comprised of keratinized stratified squamous epithelium, in
which the top superficial layers of cells are dead, and the bottom connective tissue layer
is made up of connective tissue proper, which contains many collagen fibers. Mucous membranes
line many passageways that open up to the external environment. Mucous membranes are also composed of
epithelial and connective tissue. In many areas of the body these membranes are covered with a
mucus, secreted by goblet cells that are part of the epithelial layer. Mucous membranes line
the digestive tract, respiratory tract, urinary and reproductive tracts. Serous membranes line
many of the body cavities that are not open to the external environment. Serous membranes are
comprised of simple squamous epithelium and connective tissue, and they actually have two
layers, a parietal layer and a visceral layer. In between these two layers is the serous
cavity which contains serous fluid. Serous membranes line the heart, lungs, and the abdominal
cavity, and abdominal organs, such as the stomach. Synovial membranes lines some of the joints
in the body. They are composed of connective tissue with a thin layer of synoviocyte cells.
The cells secrete synovial fluid that fills the joint cavity, which helps to reduce friction.
And that be the basics on the body membranes.