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Excretory system
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This system involves the kidneys and the liver which is not part of the system but creates most of the excreted waist
Leifang
The excretory system excretes wastes. It is responsible for the elimination of the nitrogeneous waste products of metabolism as well as other non-useful nitrogeneous materials.
Lungs are two organs localized on each side of the thorax. They are constituted by pulmonary alveoli.
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Encyclopedia
This system involves the kidneys and the liver which is not part of the system but creates most of the excreted waist
Leifang
The excretory system excretes wastes. It is responsible for the elimination of the nitrogeneous waste products of metabolism as well as other non-useful nitrogeneous materials.
Lungs are two organs localized on each side of the thorax. They are constituted by pulmonary alveoli. They are responsible for converting oxygen into carbon dioxide, but to maintain the organism's cells can take the oxygen through passive diffusion from the bloodstream and use it in its own metabolism, thus
every organism, from the smallest protist to the largest mammal, must rid itself of the potentially harmful by-products of its own vital activities. This process in living things is called elimination, which may be considered to encompass all of the various mechanisms and processes by which life forms dispose of or throw off waste products, toxic substances, and dead portions of the organism. The nature of the process and of the specialized structures developed for waste complexity of the organism.
Four terms are commonly associated with waste-disposal processes and are often used interchangeably, though not always correctly: excretion, secretion, egestion, and elimination.
The separation, elaboration, and elimination of certain products arising from cellular functions in multi-cellular organisms is called secretion. Though these substances may be a waste product of the cell producing them, they are frequently useful to other cells of the organism. Examples of secretions are the digestive enzymes produced by intestinal and pancreatic tissue cells of vertebrate animals, the hormones synthesized by specialized glandular cells of plants and animals, and sweat secreted by glandular cells in the skins of some mammals. Secretion implies that the chemical compounds being secreted were synthesized by specialized cells and that they are of functional value to the organism. The disposal of common waste products should not, therefore, be considered to be of a secretory nature.
Egestion is the act of excreting unusable or undigested material from a cell, as in the case of single-celled organisms, or from the digestive tract of multi-cellular organisms.
As defined above, elimination broadly defines the mechanisms of waste disposal by living systems at all levels of complexity. The term may be used interchangeably with excretion. The waste then travels to the anus and is released.
Skin
The skin is another part of the excretory system, containing sweat that help regulate the concentration in one’s body while also keeping him or her cool. The salt helps evaporate the water, cooling off the skin. Sweat is excreted through sweat glands. There are two types of sweat glands: eccrine sweat glands and apocrine sweat glands. The basic purpose of skin is to provide a waterproof, protective, covering for the body's complex internal environment. The skin also plays a key role in helping to maintain the circulatory and nervous system.
Liver
The liver is an accessory of the digestive system. It usually weighs more than 1.5 kg when fully matured. It also helps in excreting wastes from the body in a variety of processes. Laboratory analysis reveals a high concentration of a small organelle called a peroxisome, responsible for breakdown of several toxic substances.
The liver absorbs drugs and other poisonous substances in the blood. It changes the chemical structure of these substances and are then excreted in the bile. The bile is secretion of the liver. It makes digestion of fats easier and also carries away waste production.
Kidney
The key organs in the excretory system of vertebrates are the kidneys. Please see protonephridia system for Platyhelminthes, metanephridia for Annelida, or the Malpighian tubes for Insects and terrestrial arthropods. The kidneys are placed on either side of the spinal column near the lower back. They are responsible for removing nitrogenous wastes from the blood and they also regulate blood pressure in a process called osmoregulation and also assist with the production of red blood cells. The kidneys filter the blood and remove any wastes.
The kidney filters via its three layers of transport epithelia called the cortex, the medulla and the pelvis. In the cortex and medulla there are nephrons. These nephrons comprise of a glomerulus, a Bowman's Capsule, a proximal convoluted tubule, the descending and ascending Loop of Henle, the distal convoluted tubule and collecting ducts. The collecting ducts come together in the pelvis. When your body gets ready to pass waste products, it goes through the kidneys and mixes with water and urine. Then, the aqueous waste travels into the bladder. The tubes responsible for transport are known as ureters. The urea is stored in the bladder until excretion is either imperative or convenient. This occurs in a well-known process known as urination. When this happens, a tube called the urethra deposits the urine somewhere outside of the body. It also produces bile.
See also
- Major systems of the human body
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