Courses
Courses for Kids
Free study material
Offline Centres
More
Store Icon
Store

Appendix: Structure, Function & Importance

share icon
share icon
banner

Where Is the Appendix Located and What Does It Do?

There are a few vestigial organs in our body. Many of them had proper functions in the past but they have lost significance in the present due to evolution. One such organ is the appendix. It is also known as the vermiform appendix. In this section, we will learn more about its anatomy and explore the various aspects.  We will find out the importance of this organ and the ailments related to it. It is a part of the large intestine but has no function whatsoever to elaborate. Keep on reading to find what the appendix is and what its functions are.

What is the Appendix?

The vermiform appendix or the appendix is a pouch-like structure that can be found attached to the large intestine. The large intestine, as we all know, is the portion of the digestive system where the small intestine ends and empties all its content for final absorption and excretion. It is 8-10 cm long and 1.5 cm wide. It has a small cavity that narrows down and closes when it joins the large intestine. As per the appendix structure, it has muscular walls that were supposed to be used for expelling mucus secretion.

As per its anatomical shape, it can be found attached to the cecum, the first part of the large intestine that connects with the small intestine. The small elongated pouch-like structure protruding from the cecum wall is called the vermiform appendix.

The function of this organ has not been specifically clear to us to date. This is the reason why the appendix is considered to be a vestigial organ. As per research and conclusions, this organ was used as a harvesting location for gut flora and fauna. This is why it is thought to be the rebooting system for the digestive system as it might have been used to restore the gut flora and fauna. When the digestive system is hit by a parasitic microbial invasion, this part is suspected to be restoring the gut and stabilizing the colonies of the friendly bacteria residing in the digestive system.

It has been useless and does not show any kind of function in the contemporary human anatomy. Due to evolution, this organ has lost its job and we do not have the proper information to solidly concluded its functions.

What are the Proposed Functions of the Appendix?

As per the physiology of appendix, the researchers suggest that it was the birthplace of friendly bacteria residing and helping humans to maintain a proper digestive function symbiotically. When any digestive disorder occurred, this organ regenerated the gut flora and fauna and restored the gut functions properly.

It has also been proposed by observing the appendix anatomy that it might have been the cradle for the production of the endocrine cells in the fetal condition. The endocrine cells are important for the formation and secretion of different biochemical compounds that are important for the functioning and growth of different organs in a growing child inside the mother’s womb. The researchers also suggest that the appendix functioned as the organ for maintaining homeostasis.

As per another analogy of the anatomy and physiology of appendix, this organ might have been a part of the human immune system. Scientists suggest that it can also have performed as an organ restoring the immune system balance by producing leukocytes in response to the presence of antigens. It might have helped the formation of antibodies for the overall protection of the organ systems from any infection. The appendix might have played an important role in modulating the immune response of the human body.

The Fate of Appendix

Now that you have learned the possible vermiform appendix function of the appendix as suggested by the experts, you must know that the shape and size of this organ are continuously decreasing from one generation to the other. Although the rate of reduction in size and volume of the appendix is slow, it will take time to properly disappear from the digestive system of the human body.

This pouch-like organ is connected to the wall of the cecum and has no function whatsoever. Despite the fact, when it gets blocked for any reason, it causes appendicitis, an inflammation disease.

What is Appendicitis?

As per the anatomy and physiology of appendicitis, when the cavity is blocked, the inner content remains trapped and does not get released. This blockage can lead to the swelling of this organ. It takes a bulbous shape and causes pain in the abdominal region. As per the experts, the prime reason for such blockage is the formation of hardened faecal matter in the location where the appendix opens in the large intestine.

When the appendix does not find a way to empty the content, it causes distension in the organ resulting in pain and discomfort. When it remains in this way for a long time, the blood vessels close and the tissue suffers from necrosis. The bacterial growth starts to escalate causing infection and eventually it ruptures causing serious health issues. Proper diagnosis and treatment can cure the inflammation. The doctors suggest exploring the vermiform appendix location and extract it via invasive procedures. It eliminates the future possibilities of infection.

Want to read offline? download full PDF here
Download full PDF
Is this page helpful?
like-imagedislike-image

FAQs on Appendix: Structure, Function & Importance

1. What is the basic structure and location of the human appendix?

The human appendix, also known as the vermiform appendix, is a narrow, worm-shaped tube connected to the large intestine. It is a blind-ended pouch that projects from the cecum, which is the beginning of the large intestine. Typically, it measures between 5 to 10 cm in length. Its wall contains a significant amount of lymphoid tissue, which is a key part of the body's immune system.

2. Is the appendix a useless organ? Explain its main functions.

While historically considered a useless or vestigial organ, recent research indicates the appendix does have functions. Its two primary proposed roles are:

  • Immune Function: The appendix is rich in gut-associated lymphoid tissue (GALT), which helps the body fight pathogens and plays a role in mucosal immunity.
  • Microbiome Reservoir: It may act as a 'safe house' for beneficial gut bacteria, storing a sample of the microbiome that can help repopulate the gut after illnesses like diarrhoea.

3. Why is the appendix often described as a vestigial organ?

The appendix is considered vestigial because its current functions are thought to be significantly reduced compared to its role in our evolutionary ancestors. In herbivorous mammals, a larger version of the appendix (and cecum) is vital for digesting tough plant material like cellulose. As human diets evolved to include more easily digestible foods, this function became less critical, and the organ reduced in size and importance over generations.

4. What is the importance of the appendix in the digestive system?

The importance of the appendix in the human digestive system is subtle but significant. It does not play a direct role in digesting or absorbing nutrients. Instead, its main importance lies in maintaining the health of the digestive tract by supporting the immune system and preserving a healthy balance of gut flora. It acts as a storage site, protecting beneficial bacteria from being flushed out and helping to restore digestive health.

5. What causes appendicitis and why is a ruptured appendix dangerous?

Appendicitis is the inflammation of the appendix, typically caused by a blockage in the opening of the appendix. This blockage can be due to hardened stool, infection, or foreign bodies. The blockage traps mucus and bacteria inside, leading to swelling, high pressure, and infection. A ruptured appendix is extremely dangerous because it releases infectious material, pus, and stool into the abdominal cavity, causing a life-threatening infection called peritonitis.

6. How does the human appendix compare to the appendix in other animals?

The structure and function of the appendix vary greatly across the animal kingdom. In many herbivores, such as rabbits, the appendix is a large and vital organ essential for breaking down cellulose with the help of symbiotic bacteria. In contrast, the human appendix is much smaller. This comparison provides strong evidence for its vestigial nature in humans, highlighting how its function has diminished as our diet has changed from our herbivorous ancestors.

7. Can a person live a normal, healthy life without an appendix?

Yes, a person can live a completely normal and healthy life after the surgical removal of the appendix (an appendectomy). While the appendix has identified functions related to immunity and the microbiome, its removal does not cause any noticeable long-term health problems. Other parts of the body's extensive immune system and the vast population of gut bacteria in the colon effectively compensate for its absence.