The urinary tract is that of the set of organs and deputy structures that allow for the production as well as the elimination of urine. This is the passage from the pelvis of the kidney through the ureters, bladder, and urethra to the external urinary opening.
What is the urinary tract?
The urinary tract, via the function of different organs that compose it, is engaged in the production and elimination of urine. It is formed by the kidneys, the ureter, the bladder and urethra.
Kidneys
The kidneys main function is the production of urine. In the human body are contained two kidneys which are positioned on either side of the spine, between the eleventh thoracic vertebra and the third secondary lumbar. The right kidney is located just below the liver, while the left kidney is located behind the spleen (the two areas which are known as the lumbar). They are approximately 12 cm along, and are characterized by a form that resembles that of a bean, their weight is around 100 to 130 grams each.
The ureter
The ureter is the conduit that allows the urine to pass from the kidneys to the urinary bladder. Present in each of the two kidneys, it is a mucosal duct muscle which can ideally be divided into an abdominal portion and a pelvic portion. The two ureters are arranged at the sides of the vertebral column, vertically. Their diameter measure to about one centimeter, while the length is approximately 25 to 30 cm. They are coated internally by a wall of mucosa which comes into contact with the urine, this wall is, in turn, covered by a cowl muscle, contracting, which causes the expulsion of urine in the bladder. Each ureter has, in its lower end, in the outlet in the wall of the bladder, a valve which allows urine to flow into the bladder but which prevents the revers path, henceforth preventing the flow of urine back towards the kidneys.
The urethra
The urethra is the channel that puts in communication the bladder with that of the orifice (meatus) urethra. It is characterized by different functions and morphologies in the two sexes; in fact in the female anatomy its unique feature is to allow for the expulsion of urine outside the body, while in males it is instead the maximal expiratory pressure (MEP), which in addition to transport of the urine to the outside body, also transports the semen. The mean diameter of this conduit is about 10 mm, however in both males and females the length varies significantly.
The urinary bladder
The urinary bladder, which is shaped like a ball, accumulates the urine produced by the kidneys. It receives the two ureters (i.e. the tubes that carry urine from the kidneys to the bladder) and expels urine through the urethra. The urinary bladder is placed differently in women and men due to the physical anatomy of the sexes. In the female body it is positioned under the peritoneum, in front of the uterus, while in the male anatomy it is located above the prostate and before the rectum.
What function does the urinary tract serve?
The functions of the urinary tract system is to allow for the production and elimination of urine from the body.
