Bladder

The bladder is a hollow organ of the human urinary system. It is located directly in the cavity of the small pelvis, from behind in relation to the lump articulation. Consider this anatomical structure in more detail, and we will call the main functions of the bladder.

How does this body work in humans?

The bladder has almost the same structure, both in men and in women. However, in the stronger sex immediately behind the bladder is the rectum, which adjoins it. In women behind this capacious organ is the vagina. It must also be said that the ladies have a urogenital diaphragm beneath the bladder, and the prostate gland in men.

In the external structure of the bladder, it is customary to separate the anterior, posterior and lateral walls. At the same time, due to its anatomical features, the upper part of the organ is much more mobile than the lower one. the latter is fixed by bundles. When the bladder is filled with urine, its upper wall rises and protrudes above the pubis. At the same time, the peritoneum is raised, and the bladder changes its shape and resembles a large egg.

The lower, broader part of the bladder, called the bottom, faces down and back in relation to the rectum. The middle part of this organ, called the body, gradually tapering towards the anterior abdominal wall, forms the so-called tip of the bladder. In the anterior part of the bottom are 3 holes: 2 mouths of the ureters and the third is the urethra.

Considering the structure of the human bladder, one can not help mentioning what its walls are. Outside they are covered with a mucous membrane, under which the submucosa is located. The next layer is the muscle and serosa. In this case, the mucous surface is lined with a transitional epithelium, which causes the so-called folding. It is at her expense, the volume of this body, can increase several times.

The muscular membrane of the organ is represented by longitudinal, circular and internal oblique-longitudinal layers of smooth muscles, which are closely intertwined. In this case, the middle layer in the region of the neck of the bladder (the part where its narrowing occurs) surrounding the internal opening of the urethra forms an internal sphincter. It is this entity that is responsible for the retention of urine inside the bladder.

If we compare the structure of the bladder in women and men, it is necessary to note the following distinctive features:

• in men it is higher in the small pelvis, in women it is lower;
• in women - in front of the vagina and ureters, in men between the pubic bone and rectum;
• length of the female urethra - 3-4 cm, male - about 20 cm.

What is a bladder for?

Despite its relatively simple structure, this body plays an important role in the human body. Based on the structure of the bladder, you can name its main functions and purpose. Among them are:

• reservoir;
• evacuation.

So, the first is to collect and store urine. It is established that the average physiological capacity of this organ is 200-400 ml (due to the stretching of the walls of urine, it will interfere significantly more). It should also be taken into account that in people aged due to the weakening of the muscle layer of the bladder, its volume increases.

The evacuation function of the organ is carried out due to the contractile movement of the muscle fibers of the bladder, and also as a result of an irritant effect on the mechanoreceptors of the urethra.

Also among the functions can be called the indirect participation of the body in maintaining the constancy of the internal environment of the body, by removing the products of metabolism.