We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is a Serous Membrane?

By Victoria Blackburn
Updated May 23, 2024
Our promise to you
InfoBloom is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At InfoBloom, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

A serous membrane is a thin membrane that helps body parts move more easily and reduces friction between them. Also known as serosa, these membranes are found throughout the body, usually surrounding organs. There are several medical conditions associated with the serous membane, some of which can be life threatening.

Characteristics and Location

Serosa are made up of two layers of tissue with a thin layer of serous fluid in the middle. One layer is made up of mesothelium, which produces the fluid, while the other is made up of connective tissue, which attaches the membrane to other parts of the body and provides blood and nerves for the epithelial layer. Serous fluid itself is a thin liquid that's normally pale yellow, but can become milky, dark yellow, or red in people with infections or other medical conditions.

Many places in the body have serosa, including the body cavities surrounding the heart, lungs, and the abdomen and pelvic area. It's also found in the stomach, uterus, testicles, and vagina. Depending on where the membrane is located in the body, it may be called different things: for instance, the serous membrane around the heart is called the pericardium, while that around the lungs is called the pleura, and that surrounding the testes is called the tunica vaginalis.


Though all serosa are primarily used for reducing friction, their exact function differs slightly by location. The pericardium, for example, makes it easy for the heart to expand and contract as it beats as well as protecting is and holding it in place. Similarly, the pleura makes it easier for the lungs to expand by reducing friction between them and the surrounding tissues, but also makes the outer layer of the lungs cling to the surrounding tissue, which helps keep them from collapsing inwards.

Related Problems

Problems with a serous membrane can be related to the serous fluid or to the two tissue layers. An overproduction of fluid can cause serious problems, especially if enough fluid is produced to put pressure on a person's organs. This is called effusion when it happens around the heart or lungs, and ascites if it happens in the peritoneum. All three can be life-threatening if not treated promptly, and usually have to be treated by draining the fluid with a needle. Serous fluid can also become infected with bacteria or mixed with blood because of a problem somewhere else in the body.

Another condition that affects the tissue layers of the serous membrane, rather than the fluid, is malignant mesothelioma. This is a cancer that most often affects the pleura, though it can affect any of the serosa. It's primarily associated with exposure to asbestos, and is generally very difficult to treat.

InfoBloom is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.

Discussion Comments

By anon253611 — On Mar 10, 2012

What would happen if the serous membrane lined the gut?

By anon235881 — On Dec 20, 2011

Thanks so much! This was a huge help! I'm cramming for an RN exam and this helped me out a lot!

By anon124190 — On Nov 04, 2010

thanks a lot. Your articles help me especially in my anatomy assignment and physiology.

suleiman m., from windsor university school of medicine

By anon71989 — On Mar 21, 2010

my name is brian. i want to say thanks a lot for this article. it really helped me with my assignment about body membranes in my anatomy assignment.

By randolfh — On Jan 08, 2010

i'm Randolf.. thanks for the article "serous membranes." It helped me here in my research about the four types of epithelial membranes. i found the article informative and that's why i joined your community.

as a student it really pays to have a reliable reference to equip me with knowledge. i major in biology so that's why i found it a must for me to get accurate information about life's questions. thanks again for the warm welcome. i like your website. it's great.

InfoBloom, in your inbox

Our latest articles, guides, and more, delivered daily.

InfoBloom, in your inbox

Our latest articles, guides, and more, delivered daily.