Excretory system


Digestive System
Urinary Incontinence in Children Should I take my child to the doctor? It's never too late to improve your sex life. Click To View Large Image. In women, approximately in 10, cases are treated as outpatients and cases are admitted to a hospital. Electromyography may be performed. Bladder training also includes Kegel exercises to strengthen the pelvic muscles, which help hold urine in the bladder.

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Urinary Incontinence in Men

A pigment, bilirubin , formed in the process of hemoglobin breakdown, is released into the bile, creating its characteristic greenish orange colour, and is excreted from the body through the intestine. The liver cells synthesize a number of enzymes. As blood flows through the liver, both from the portal vein and from the hepatic artery , the cells and enzymes are filtered.

Nutrients entering the liver from the intestine are modified into forms that are usable by the body cells or are stored for future use. Fats are converted into fatty acids and then into carbohydrates or ketone bodies and transported by the blood to the tissues, where they are further metabolized. Sugars are converted into glycogen, which remains stored in the liver until it is needed for energy production; it is then reconverted into glucose and released into the bloodstream.

The liver manufactures blood serum proteins, including albumin and several clotting factors, and supplies them to the blood. The liver also metabolizes nitrogenous waste products and detoxifies poisonous substances, preparing them for elimination in the urine or feces.

A common sign of impaired liver function is jaundice , a yellowness of the eyes and skin arising from excessive bilirubin in the blood. Jaundice can result from an abnormally high level of red blood cell destruction hemolytic jaundice , defective uptake or transport of bilirubin by the hepatic cells hepatocellular jaundice , or a blockage in the bile duct system obstructive jaundice. Failure of hepatic cells to function can result from hepatitis , cirrhosis , tumour s, vascular obstruction, or poisoning.

Symptoms may include weakness, low blood pressure , easy bruising and bleeding, tremor, and accumulation of fluid in the abdomen. Blood tests can reveal abnormal levels of bilirubin, cholesterol , serum proteins, urea , ammonia , and various enzymes. A specific diagnosis of a liver problem can be established by performing a needle biopsy. The liver is subject to a variety of other disorders and diseases.

Abscesses can be caused by acute appendicitis ; those occurring in the bile ducts may result from gallstone s or may follow surgery. The parasite that causes amebic dysentery in the tropics can produce liver abscesses as well. Various other parasites prevalent in different parts of the world also infect the liver. Liver cancer is common, occurring mostly as secondary tumours originating elsewhere in the body.

Glycogen-storage diseases , a group of hereditary disorders, generate a buildup of glycogen in the liver and an insufficient supply of glucose in the blood. Certain drugs may damage the liver, producing jaundice.

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The resulting disorders usually affect one of the three functional components: This "pelviureteric junction" is a common site for the impaction of kidney stones the other being the uteterovesical valve.

The ureters run posteriorly on the lateral walls of the pelvis. They then curve anteriormedially to enter the bladder through the back, at the vesicoureteric junction, running within the wall of the bladder for a few centimeters. The backflow of urine is prevented by valves known as ureterovesical valves.

In the female, the ureters pass through the mesometrium on the way to the bladder. The urinary bladder is the organ that collects waste excreted by the kidneys prior to disposal by urination.

It is a hollow muscular , and distensible or elastic organ, and sits on the pelvic floor. Urine enters the bladder via the ureters and exits via the urethra. Embryologically, the bladder is derived from the urogenital sinus , and it is initially continuous with the allantois. In human males, the base of the bladder lies between the rectum and the pubic symphysis. It is superior to the prostate , and separated from the rectum by the rectovesical excavation.

In females, the bladder sits inferior to the uterus and anterior to the vagina. It is separated from the uterus by the vesicouterine excavation. In infants and young children, the urinary bladder is in the abdomen even when empty. In anatomy, the from Greek — ourethra is a tube which connects the urinary bladder to the outside of the body.

In humans, the urethra has an excretory function in both genders to pass. One of the main functions of the lungs is to diffuse gaseous wastes, such as carbon dioxide, from the bloodstream as a normal part of respiration. The large intestine's main function is to transport food particles through the body and expel the indigestible parts at the other end, but it also collects waste from throughout the body. The typical brown colour of mammal waste is due to bilirubin , a breakdown product of normal heme catabolism.

At about 10 feet long in humans, it transports the wastes through the tubes to be excreted. The liver detoxifies and breaks down chemicals, poisons and other toxins that enter the body.

For example, the liver transforms ammonia which is poisonous into urea in fish , amphibians and mammals, and into uric acid in birds and reptiles. Urea is filtered by the kidney into urine or through the gills in fish and tadpoles.

Uric acid is paste-like and expelled as a semi-solid waste the "white" in bird excrements. The liver also produces bile , and the body uses bile to break down fats into usable fats and unusable waste.

Invertebrates lack a liver, but most terrestrial groups, like insects , possesses a number of blind guts that serve the similar functions. Marine invertebrates do not need the ammonia conversion of the liver, as they can usually expel ammonia directly by diffusion through the skin. Sweat glands in the skin secrete a fluid waste called sweat or perspiration ; however, its primary functions are temperature control and pheromone release. Therefore, its role as a part of the excretory system is minimal.

Sweating also maintains the level of salt in the body. The sweat, helped by salt, evaporates and helps to keep the body cool when it is warm. In amphibians, the lungs are very simple, and they lack the necessary means to the exhale like other tetrapods can. The moist, scale-less skin is therefore essential in helping to rid the blood of carbon dioxide , and also allows for urea to be expelled through diffusion when submerged.

In small-bodied marine invertebrates, the skin is the most important excretory organ. That is particularly true for acoelomate groups like cnidarians , flatworms and nemerteans , who have no body cavities and hence no body fluid that can be drained or purified by nephrons, which is the reason acoelomate animals are thread-like nemertans , flat flatworms or only consist of a thin layer of cells around a gelatinous non-cellular interior cnidarians.

Like sweat glands, eccrine glands allow excess water to leave the body. The majority of eccrine glands are located mainly on the forehead, the bottoms of the feet, and the palms, although the glands are everywhere throughout the body.

They help the body to maintain temperature control. Eccrine glands in the skin are unique to mammals. Secretions of sweat from the eccrine glands play a large role in controlling the body temperature of humans.

The two functions consist of secretion of a filtrate in response to acetylcholine and reabsorption of sodium near the duct when there is water in excess so that a sweat can be surfacing the skin. There are three parts to the eccrine sweat gland and these are the pore, the duct, and the gland. The pore is the portion that goes through the outermost layer of the skin and is typically microns in diameter.

The duct is the part of the sweat gland that connects dermis cells to the epidermis. It is composed by two layers of cells and is between 10 and 20 microns in diameter. The gland does the actual secretion and it lies deep within the dermis. The cells that make up the gland are larger in size than the duct cells and its lumen is around 20 microns in diameter.

After bile is produced in the liver, it is stored in the gall bladder. It is then secreted within the small intestine where it helps to emulsify fats in the same manner as a soap. Bile also contains bilirubin , which is a waste product.

Bile salts can be considered waste that is useful for the body given that they have a role in fat absorption from the stomach. They are excreted from the liver and along with blood flow they help to form the shape of the liver where they are excreted.

For instance, if biliary drainage is impaired than that part of the liver will end up wasting away. Biliary obstruction is typically due to masses blocking the ducts of the system such as tumors. The consequences of this depend on the site of blockage and how long it goes on for. There is inflammation of the ducts due to the irritation from the bile acids and this can cause infections. If rupture of the duct takes place it is very traumatic and even fatal.

Within the kidney, blood first passes through the afferent artery to the capillary formation called a glomerulus and is collected in the Bowman's capsule , which filters the blood from its contents—primarily food and wastes.

After the filtration process, the blood then returns to collect the food nutrients it needs, while the wastes pass into the collecting duct, to the renal pelvis, and to the ureter, and are then secreted out of the body via the urinary bladder. When substances are not properly dissolved, they have the ability to build up, and form these kidney stones. These stones are most commonly made up of substances such as calcium, cystine, oxalate, and uric acid, as these are the substances that normally would dissolve within the urine.

When they do not dissolve correctly and further build up, they will commonly lodge themselves in the urinary tract and in this case, are usually small enough to pass through urine. In extreme situations, however, these stones may lodge themselves within the tube that connects the kidney and the bladder, called the ureter. In this case, they become very large in size and will most likely cause great pain, bleeding, and possibly even block the flow of urine.

In those extreme situations, in which kidney stones are too large to pass on their own, patients may seek removal. Most of these treatments involving kidney stone removal are done by a urologist; a physician who specializes in the organs of the Urinary system.

Digestive System Physiology