Some information about urinary and colorectal functions

About the urinary system and its functions

The kidneys: The kidneys are situated high up in the posterior part of the abdomen at each side and they are hidden beneath the peritoneum and polstered by fatty tissue. A think blood vessel goes from  the main artery in the body, the aorta, to each kidney and a thick vein goes back from the kidney to the main vain of the body, the vena cava.

The kideneys filter out excessive fluid and excessive salts from the blood and thereby from the whole body. The kidneys also filter out vaste products from the bodily metabolism that are circulating in the blood, which mainly is in the form of urea.

In the kidneys there are several bundles of ducts that branch into extremely fine branches. All these ducts convert into greater ducts that ends in a greater cavity for urine collection in each kidney. Also the arteries that enter the kidneys branch into very fine branches that enter the walls of the end parts of these ducts, and continues as a vein that follows each duct some distance downstream.

At the end of the fine ducts, nearly pure blood plasma seeps through the blood vessel walls into the duct. In the way downwards some water  and salts that the body needs is reabsorbed into the blood vessel, so that only those elements that the body does not need is vasted as elements in the urine.

The urethers: From the hollow area in each kidney a tube called the urether descends downwards towards the bladder. Each urether have a nuscular wall that is able to contract in a wavelike fashion just as the intestines. The urethers conduct urine downwards by means of contractions by the muscuklar elements in the urethers. At the place where the urethers enter the bladder, there is a valve-like construction capable of hindering the urine from being pressed up again towards the kidneys.

The bladder: The bladder is as strong sack with a robust muscular wall and with an inner mucosa. The bladder collects the urine in a pasive way, but when the bladder gets filled up to some point, there will be some tension in the bladder wall accompanied with feelings of urge to pee. During urination the tension increases and the bladder presses the urine out actively.

The urethra: The urethra is the tube leading the urine out. Just under the bladder there is a strong muscular bundle with fibers going in many crossing directions, the urethral spincter. There is normally some automatic tension in the urethral spincter that hinders urine from seeping out from the bladder. A person also has the ability to tense the spincter and other muscles along the urethra even more at free will when the bladder is full and he does not want to urinate yet.

There is also some elastic tension in the urethra and the surrounding tissues that also hinders urine from leaking out. During urination the spincter relaxes totally so that the bladder can press the urine out. When this happpens the pressure from the bladder overcomes the tension in the urethra and the urine finds its way out. The controle of the spincter function is a complicated interplay of voluntary and automatic mechanisms. Along the inner part of the urethra there is are lot of glands that produce slime to lubricate the urethra and hinders the urethral wall to glue together.

In a male also the ducts form the prostate and testicles enter the urethra just beneath the spincter, and the urethra is also the channel through which the semen is pumped out during intercource or masturbation. When the penis is fully erect, and especially during ejaculation of semen, the spincter will close, so that urine does not leak out.

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These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease. This information is nutritional in nature and should not be construed as medical advice. This notice is required by the Federal Food, Drug and Cosmetic Act.