Excretion is the process of eliminating waste products of metabolism and other non-useful materials. Metabolism is the set of Chemical reactions that occur in living Organisms in order to maintain Life. [1] It is an essential process in all forms of life. It contrasts secretion, where the substance may have specific tasks after leaving the cell. Secretion is the process of segregating elaborating and releasing chemicals from a cell, or a secreted Chemical substance or amount of substance
In single-celled organisms, waste products are discharged directly through the surface of the cell. A microorganism (also spelled micro organism or micro-organism and also called a microbe) is an Organism that is Microscopic (usually The cell is the structural and functional unit of all known living Organisms It is the smallest unit of an organism that is classified as living and is often called Multicellular organisms utilize more complex excretory methods. Multicellular organisms are Organisms consisting of more than one cell, and having Differentiated cells that perform specialized functions Higher plants eliminate gases through the stomata, or pores, on the surface of leaves. Plants are living Organisms belonging to the kingdom Plantae. In Botany, a stoma (also stomate; plural stomata) is a tiny opening or pore found mostly on the underside of a Plant Leaf Animals have special excretory organs.
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Human excretion
In humans, the two major excretory processes are the formation of urine in the kidneys and the formation of carbon dioxide (a human's abundant metabolic waste) molecules as a result of respiration, which is then exhaled from the lungs. The kidneys are complicated organs that have numerous biological roles Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Metabolism is the set of Chemical reactions that occur in living Organisms in order to maintain Life. These waste products are eliminated by urination and exhalation respectively. In urination, hormonal control over excretion occurs in the distal tubules of the kidneys as directed by the hypothalamus.
In kidney
In humans the main organs of excretion are the kidneys and accessory urinary organs, through which urine is eliminated,[2] and the large intestines, from which solid wastes are expelled. In Medicine, the clearance is a measurement of the renal Excretion ability The kidneys are complicated organs that have numerous biological roles The urinary system (also called Excretory system or the genitourinary system (GUS is the Organ system that produces stores and eliminates Urine. Urine is a liquid waste product of the body secreted by the Kidneys by a process of filtration from Blood and Excreted through the Urethra. The large intestine is the last part of the Digestive system: the final stage of the Alimentary canal in Vertebrate Animals Its function is to Feces, faeces, or fæces (see spelling differences) is a waste product from an animal's digestive tract expelled through the Anus In strict biological terminology, the expulsion of feces is not considered to be excretion, since faeces is indigestible food, and not metabolic waste. Feces, faeces, or fæces (see spelling differences) is a waste product from an animal's digestive tract expelled through the Anus The skin and lungs also have excretory functions: the skin eliminates water and salts in sweat,[3] and the lungs expel water vapor and carbon dioxide. The skin is the outer covering of living tissue of an animal (or plant lung is the essential Respiration organ in air-breathing Animals including most Tetrapods a few Fish and a few Snails The most primitive Salt is a Dietary mineral composed primarily of Sodium chloride that is essential for Animal life but toxic to most land plants General properties of water vapor Evaporation/sublimation Whenever a water molecule leaves a surface it is said to have evaporated Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single
Other
- Mucociliary excretion is the excretion of mucus in the respiratory system. In vertebrates mucus is a slippery secretion produced by and covering Mucous membranes It is a viscous Colloid containing Antiseptic enzymes (such as In living organisms a respiratory system functions to allow Gas exchange.
Non-human
Plants have been shown (by British biologist Brian J. Ford) to translocate wastes into leaves which are then shed. Brian J Ford (born 1939 in Corsham, Wiltshire) is an independent research biologist and left before graduating to set up his own multi-disciplinary laboratory In this fashion, the leaf, in addition to acting as an energy-trapping structure, is also a plant's organ of excretion. Photosynthesis is a Metabolic pathway that converts Light Energy into Chemical energy.
Aquatic animals usually excrete ammonia directly into the external environment, as this compound has high solubility and there is ample water available for dilution. An aquatic animal is an Animal which lives in water for most or all of the time Ammonia is a compound with the formula N[[hydrogen H3]] It is normally encountered as a Gas with a characteristic pungent Odor Solubility is the characteristic Physical property referring to the ability of a given substance the Solute, to dissolve in a Solvent. In terrestrial animals ammonia-like compounds are converted into other nitrogenous materials as there is less water in the environment and ammonia itself is toxic. Terrestrial animals are Animals that live predominantly or entirely on land as compared with Aquatic animals which live predominantly or entirely in the water (e Toxicity is the degree to which a substance is able to damage an exposed organism
Most mammals excrete nitrogenous wastes in the form of urea, an ancestral trait. Mammals ( class Mammalia) are a class of Vertebrate Animals characterized by the presence of Sweat glands, including sweat glands Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 Urea is an Organic compound with the Chemical formula ( N[[hydrogen H]]22 C[[oxygen O]]
Birds excrete their nitrogenous wastes as uric acid in the form of a paste. Birds ( class Aves) are bipedal endothermic ( Warm-blooded) Vertebrate animals that lay eggs. Uric acid (or urate) is an Organic compound of Carbon, Nitrogen, Oxygen and Hydrogen with the formula C5H4N4O3 This is metabolically more expensive, but allows more efficient water retention and it can be stored more easily in the egg. Water is a common Chemical substance that is essential for the survival of all known forms of Life. In most Birds and Reptiles an egg ( Latin ovum) is the Zygote, resulting from Fertilization of the Ovum. Many avian species, especially seabirds, can also excrete salt via specialized nasal salt glands, the saline solution leaving through nostrils in the beak. Seabirds are Birds that have adapted to life within the marine environment Anatomy Stegosaurus --> Beaks can vary significantly in size and shape from species to species
Perspiration is another excretory process which removes salts and water from the body, although the primary purpose is cooling.
In insects, a system involving Malpighian tubules is utilized to excrete metabolic waste. Insects ( Class Insecta) are a major group of Arthropods and the most diverse group of Animals on the Earth with over a million described The Malpighian tubule system is a type of Excretory and osmoregulatory system found in some Uniramia ( Insects and Myriapoda) Metabolic wastes or excretes are Substances left over from respiratory processes which cannot be used by the Organism (they are surplus or have Metabolic waste diffuses or is actively transported into the tubule, which transports the wastes to the intestines. The metabolic waste is then released from the body along with fecal matter.
Etymology
Many people misuse the term excretion as a euphemism for defecation, and use excrement for feces, but this is medically inexact. Defecation is the final act of Digestion by which organisms eliminate solid semisolid or liquid Waste material ( Faeces) from the Digestive tract Feces, faeces, or fæces (see spelling differences) is a waste product from an animal's digestive tract expelled through the Anus [1]
References
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Countercurrent exchange is a mechanism used to transfer some property of a Fluid from one flowing current of fluid to another across a Semipermeable membrane or thermally-conductive Flatulence is the production of a mixture of gases in the digestive tract of Mammals that are byproducts of the digestion process Homeostasis (from Greek: ὅμος hómos, "equal" and ιστημι istēmi, "to stand" lit Osmoregulation is the active regulation of the Osmotic pressure of bodily fluids to maintain the Homeostasis of the body's Water content that is it keeps In Animal physiology, respiration is the transport of Oxygen from the outside air to the cells within tissues and the transport of Carbon dioxideDapyx Software network: MP3 Explorer | Ebook Manager | Zenithic