Task of the appendix


The appendix is ​​the beginning of the large intestine, which begins blind in the right lower abdomen. The appendix in humans is quite short and only measures about 10 cm.On its side, the small intestine and the large intestine are connected. The blind end goes into a narrow, tail-shaped extension, the so-called appendix, above. This small appendix is ​​often incorrectly called the appendix.

The function of the appendix is ​​by no means restricted to digestion. It also plays a role for the immune defense in the intestine that should not be underestimated.

Figure appendix with appendix
  1. Appendix - Caecum
    (Light blue border)
  2. Opening the Bauhin flap -
    Ostium ileal
  3. Mouth of the appendix -
    Ostium appendicis vermiformis
  4. Free tape strip -
    Taenia libera
  5. Appendix -
    (Light green border)
    Appendix vermiformis
  6. End part of the ileum -
    Ileum, pars terminalis
  7. Ileum-appendix valve
    (Bauhin flap) -
    Ileal papilla
  8. Transverse folds of the colon -
    Plicae semilunares coli
  9. Colon, ascending part - Ascending colon

You can find an overview of all Dr-Gumpert images at: medical illustrations

Digestive tasks

Compared to the other parts of the intestine, the appendix has one for digestion little importance. The nutrients from the food have already been absorbed in the small intestine in front of it. It is in the large intestine Main task in the Reabsorption of water from stool and its thickening. At the same time, electrolytes are also used, especially Sodium and potassium, from the body resumed.

Since the appendix is ​​significantly larger in herbivores, it is assumed that the appendix in the Digestion of high fiber foods occupies a prominent position. These food components, which are otherwise indigestible for the body, such as cellulose, are broken down by bacteria and made usable for the body.

Furthermore, mucus is produced by the large intestine in order to facilitate the transport of the last bits of food. This transport is further supported by the bowel movements.

The entire large intestine including the appendix are in contrast to the small intestine colonized with a wide variety of bacteria. These decompose the last leftovers of food that could not be used by the body, which can lead to gas formation.

Tasks for the immune system

The appendix and especially its appendix (appendix) are With lymphatic Interspersed with tissue, whose main task is in the Immune defense lies. So you are the one Guardian between the colon populated with bacteria and the sterile small intestine. The appendix is ​​also called "Intestinal tonsil " because it is so abundantly interspersed with lymphatic tissue. This lymphatic Tissue will too Gut-associated lymphoid tissue called and performs important tasks. First of all, it produces one Antibody secretion, which protects the intestinal mucosa from microorganisms by interlinking them. This prevents these microorganisms from attaching to the intestinal cells and being able to penetrate them.

There are also so-called in the intestinal mucosa M cells, the Antigens from the intestinal contents to the cells of our immune system. This enables an immune response in our body, which is directed very specifically against the pathogens.

Another aspect of the appendix is ​​possibly one Reservoir function for intestinal bacteriaso that a healthy intestinal flora can be restored more quickly after intestinal diseases.

Original role of the appendix

As already mentioned, the appendix is ​​differently developed in different animals. It is hardly developed in carnivores, and the appendix is ​​also quite small in humans, who are omnivores.

On the other hand, it is very well trained in herbivores and has a large capacity, especially in herbivores that cannot ruminate. Rumination is important for the digestion of plant fibers. In the case of herbivores that are unable to ruminate, these plant fibers have to be broken down in the appendix so that the animal can ingest and use them. These animals then form a kind of fermentation chamber in which the food is fermented and processed. The horse is one of the animals for which this process is important.

The human being is not dependent on the digestion of fiber-rich food for its food supply, but draws its energy from other food sources that are more easily digestible and accessible to the body with less energy expenditure. Thereby is he does not depend on the appendix. In the course of evolution and changes in human nutrition, the appendix was no longer stressed. As a result, the appendix has regressed or not developed further over time. This process of evolution is a normal process of adaptation and can also be observed in other organs or parts of the body. So the tailbone is the remnant of a tail.

In addition to the digestion of fiber-rich plant components, which humans can barely digest today, the appendix of the appendix in particular still has one Role in the immune system. The appendix still has this today. However, this function can be compensated by the body if the appendix has been removed after inflammation. Because there are cells of the immune system in the other parts of the intestine. However, today's people in the western world are hardly exposed to dangerous intestinal diseases. It is conceivable that to combat such a disease that lymphatic The tissue of the appendix is ​​quite important.

Why do we still have an appendix today?

As explained in the previous section, the appendix is ​​a Remnant of evolution and has hardly any function for humans today. Because of their diet, humans are not dependent on their digestive ability of fiber-rich plant food and they can manage without the contribution of the appendix to the immune system.

In medicine, the appendix has already been removed prophylactically during abdominal surgery, as one Appendicitis can be life-threatening. However, there are always discussions in research about whether the appendix does not have important functions for the human body. Furthermore, the appendix can be used to reconstruct other organs in the case of serious illnesses.

Read more on this topic: Appendicitis

additional Information
  • appendix
  • Colon
  • Digestive tract
  • Appendicitis
  • immune system
  • Lymphatic organs