In particular, in the body of each person there is a paired organ called a ureter. In appearance, it is a hollow tube, the length of which is not more than 30 cm, and the diameter - from 4 to 7 mm. In this article we will tell you why the ureters are needed, what their structure is, and what functions this body performs.
Structure of the ureter in women and men
Ureters in the body of persons of both sexes originate from renal pelvis. Further, these tubes go down behind the peritoneum and reach the wall of the bladder, through which they penetrate in an oblique direction.
The wall of each ureter has 3 layers:
- outer shell, consisting of connective tissue;
- muscular layer;
- the mucous membrane covering the ureter from the inside.
The diameter of the ureters is a relative value and can vary quite considerably at different sites. So, in the norm each person has several anatomical narrowings of this paired organ in the following places:
- in the place of transition of the renal pelvis into the ureter;
- before the exit of the ureter into the small pelvis;
- in some places in the small pelvis or along its entire length;
- Before the entrance of each ureter into the bladder.
The length of this organ in different people can also be different, depending on gender, age and individual anatomical features of a person.
Thus, the female ureter is normally 20-25 mm shorter than the male. In a small pelvis in beautiful women this tube is forced to skirt the internal sexual organs, so it has a slightly different course.
In the beginning, the female ureters pass along the free edge of the ovaries, and then along the base of the broad ligament of the uterus. Further, these tubes along the oblique pass into the bladder in the immediate vicinity of the vagina, while at the junction a muscular sphincter is formed.
Function of the ureter in the human body
The main task that the ureters perform is the transport of urine from the renal pelvis to the bladder. The presence of a muscle layer in the wall of this organ allows it to constantly change its width under the pressure of the urine flowing into the inner cavity of the tube, as a result of which it is "pushed" inwards. In turn, urine can not return back, as part of the ureter inside the bladder serves as a valve and a fuse.