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76-400: NKCC1 is widely distributed throughout the human body; it has important functions in organs that secrete fluids. It is found specifically in the kidney , where it extracts sodium, potassium, and chloride from the urine so they can be reabsorbed into the blood . NKCC proteins are membrane transport proteins that transport sodium (Na), potassium (K), and chloride (Cl) ions across

152-731: A blood bank . There are many different blood types in humans, the ABO blood group system , and the Rhesus blood group system being the most important. Transfusion of blood of an incompatible blood group may cause severe, often fatal, complications, so crossmatching is done to ensure that a compatible blood product is transfused. Other blood products administered intravenously are platelets, blood plasma, cryoprecipitate, and specific coagulation factor concentrates. Many forms of medication (from antibiotics to chemotherapy ) are administered intravenously, as they are not readily or adequately absorbed by

228-574: A blood transfusion, because the metabolism of transfused red blood cells does not restart immediately after a transfusion. In modern evidence-based medicine , bloodletting is used in management of a few rare diseases, including hemochromatosis and polycythemia . However, bloodletting and leeching were common unvalidated interventions used until the 19th century, as many diseases were incorrectly thought to be due to an excess of blood, according to Hippocratic medicine. English blood ( Old English blod ) derives from Germanic and has cognates with

304-497: A multicellular organism , an organ is a collection of tissues joined in a structural unit to serve a common function. In the hierarchy of life , an organ lies between tissue and an organ system . Tissues are formed from same type cells to act together in a function. Tissues of different types combine to form an organ which has a specific function. The intestinal wall for example is formed by epithelial tissue and smooth muscle tissue . Two or more organs working together in

380-426: A pH below 7.35 is too acidic , whereas blood pH above 7.45 is too basic. A pH below 6.9 or above 7.8 is usually lethal. Blood pH, partial pressure of oxygen (pO 2 ) , partial pressure of carbon dioxide (pCO 2 ) , and bicarbonate (HCO 3 ) are carefully regulated by a number of homeostatic mechanisms , which exert their influence principally through the respiratory system and the urinary system to control

456-549: A similar range of meanings in all other Germanic languages (e.g. German Blut , Swedish blod , Gothic blōþ ). There is no accepted Indo-European etymology. Robin Fåhræus (a Swedish physician who devised the erythrocyte sedimentation rate ) suggested that the Ancient Greek system of humorism , wherein the body was thought to contain four distinct bodily fluids (associated with different temperaments), were based upon

532-416: A variety of organ systems . These specific systems are widely studied in human anatomy . The functions of these organ systems often share significant overlap. For instance, the nervous and endocrine system both operate via a shared organ, the hypothalamus . For this reason, the two systems are combined and studied as the neuroendocrine system . The same is true for the musculoskeletal system because of

608-687: A whole, are referred to as the Organon because logic is a tool for philosophical thinking. Earlier thinkers, such as those who wrote texts in the Hippocratic corpus , generally did not believe that there were organs of the body but only different parts of the body. Some alchemists (e.g. Paracelsus ) adopted the Hermetic Qabalah assignment between the seven vital organs and the seven classical planets as follows: Chinese traditional medicine recognizes eleven organs, associated with

684-423: Is blood plasma , a fluid that is the blood's liquid medium, which by itself is straw-yellow in color. The blood plasma volume totals of 2.7–3.0 liters (2.8–3.2 quarts) in an average human. It is essentially an aqueous solution containing 92% water, 8% blood plasma proteins , and trace amounts of other materials. Plasma circulates dissolved nutrients, such as glucose , amino acids , and fatty acids (dissolved in

760-461: Is arterial or venous blood). Most of it (about 70%) is converted to bicarbonate ions HCO − 3 by the enzyme carbonic anhydrase in the red blood cells by the reaction CO 2 + H 2 O → H 2 CO 3 → H + HCO − 3 ; about 7% is dissolved in the plasma; and about 23% is bound to hemoglobin as carbamino compounds. Hemoglobin, the main oxygen-carrying molecule in red blood cells, carries both oxygen and carbon dioxide. However,

836-418: Is associated with a large number of beliefs. One of the most basic is the use of blood as a symbol for family relationships through birth/parentage; to be "related by blood" is to be related by ancestry or descendence, rather than marriage. This bears closely to bloodlines , and sayings such as " blood is thicker than water " and " bad blood ", as well as " Blood brother ". Blood is given particular emphasis in

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912-440: Is bright red, because carbon monoxide causes the formation of carboxyhemoglobin . In cyanide poisoning, the body cannot use oxygen, so the venous blood remains oxygenated, increasing the redness. There are some conditions affecting the heme groups present in hemoglobin that can make the skin appear blue – a symptom called cyanosis . If the heme is oxidized, methemoglobin , which is more brownish and cannot transport oxygen,

988-407: Is circulated around the body through blood vessels by the pumping action of the heart . In humans, blood is pumped from the strong left ventricle of the heart through arteries to peripheral tissues and returns to the right atrium of the heart through veins . It then enters the right ventricle and is pumped through the pulmonary artery to the lungs and returns to the left atrium through

1064-480: Is dangerous to health, and severe hypoxia (saturations less than 30%) may be rapidly fatal. A fetus , receiving oxygen via the placenta , is exposed to much lower oxygen pressures (about 21% of the level found in an adult's lungs), so fetuses produce another form of hemoglobin with a much higher affinity for oxygen ( hemoglobin F ) to function under these conditions. CO 2 is carried in blood in three different ways. (The exact percentages vary depending whether it

1140-469: Is established by the Na/K-ATPase , which is an ATP -dependent enzyme . Since NKCC proteins use sodium's gradient, their activity is indirectly dependent on ATP; for this reason, NKCC proteins are said to move solutes by way of secondary active transport . There are three isoforms of NKCC2 created by alternative splicing (NKCC2A, B and F). Each one of these isoforms is expressed at different portions of

1216-426: Is formed. In the rare condition sulfhemoglobinemia , arterial hemoglobin is partially oxygenated, and appears dark red with a bluish hue. Veins close to the surface of the skin appear blue for a variety of reasons. However, the factors that contribute to this alteration of color perception are related to the light-scattering properties of the skin and the processing of visual input by the visual cortex , rather than

1292-436: Is free to bind oxygen, and fewer oxygen molecules can be transported throughout the blood. This can cause suffocation insidiously. A fire burning in an enclosed room with poor ventilation presents a very dangerous hazard, since it can create a build-up of carbon monoxide in the air. Some carbon monoxide binds to hemoglobin when smoking tobacco. Blood for transfusion is obtained from human donors by blood donation and stored in

1368-461: Is in equilibrium with lymph , which is continuously formed in tissues from blood by capillary ultrafiltration. Lymph is collected by a system of small lymphatic vessels and directed to the thoracic duct , which drains into the left subclavian vein , where lymph rejoins the systemic blood circulation. Blood circulation transports heat throughout the body, and adjustments to this flow are an important part of thermoregulation . Increasing blood flow to

1444-570: Is known as the Haldane effect , and is important in the transport of carbon dioxide from the tissues to the lungs. A rise in the partial pressure of CO 2 or a lower pH will cause offloading of oxygen from hemoglobin, which is known as the Bohr effect . Some oxyhemoglobin loses oxygen and becomes deoxyhemoglobin. Deoxyhemoglobin binds most of the hydrogen ions as it has a much greater affinity for more hydrogen than does oxyhemoglobin. In mammals, blood

1520-515: Is oxygenated and dark red when it is deoxygenated . Medical terms related to blood often begin with hemo- , hemato- , haemo- or haemato- from the Greek word αἷμα ( haima ) for "blood". In terms of anatomy and histology , blood is considered a specialized form of connective tissue , given its origin in the bones and the presence of potential molecular fibers in the form of fibrinogen . Blood performs many important functions within

1596-493: Is produced predominantly by the liver , while hormones are produced by the endocrine glands and the watery fraction is regulated by the hypothalamus and maintained by the kidney . Healthy erythrocytes have a plasma life of about 120 days before they are degraded by the spleen , and the Kupffer cells in the liver. The liver also clears some proteins, lipids, and amino acids. The kidney actively secretes waste products into

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1672-406: Is the placenta , which has evolved more than 100 times independently in vertebrates, has evolved relatively recently in some lineages, and exists in intermediate forms in extant taxa. Studies on the evolution of the placenta have identified a variety of genetic and physiological processes that contribute to the origin and evolution of organs, these include the re-purposing of existing animal tissues,

1748-529: The acid–base balance and respiration, which is called compensation. An arterial blood gas test measures these. Plasma also circulates hormones transmitting their messages to various tissues. The list of normal reference ranges for various blood electrolytes is extensive. Human blood is typical of that of mammals, although the precise details concerning cell numbers, size, protein structure , and so on, vary somewhat between species. In non-mammalian vertebrates, however, there are some key differences: Blood

1824-454: The cell membrane . Because they move each solute in the same direction, they are considered symporters . They maintain electroneutrality by moving two positively charged solutes (sodium and potassium) alongside two parts of a negatively charged solute (chloride). Thus the stoichiometry of the transported solutes is 1Na:1K:2Cl. Although squid giant axons are the only notable exception with a stoichiometry of 2Na:1K:3Cl, electroneutrality across

1900-912: The circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells , and transports metabolic waste products away from those same cells. Blood is composed of blood cells suspended in blood plasma . Plasma, which constitutes 55% of blood fluid, is mostly water (92% by volume), and contains proteins , glucose , mineral ions , and hormones . The blood cells are mainly red blood cells (erythrocytes), white blood cells (leukocytes), and (in mammals) platelets (thrombocytes). The most abundant cells are red blood cells. These contain hemoglobin , which facilitates oxygen transport by reversibly binding to it, increasing its solubility. Jawed vertebrates have an adaptive immune system , based largely on white blood cells. White blood cells help to resist infections and parasites. Platelets are important in

1976-405: The clotting of blood. Blood is circulated around the body through blood vessels by the pumping action of the heart . In animals with lungs , arterial blood carries oxygen from inhaled air to the tissues of the body, and venous blood carries carbon dioxide, a waste product of metabolism produced by cells, from the tissues to the lungs to be exhaled. Blood is bright red when its hemoglobin

2052-428: The erectile tissue in the penis and clitoris . Another example of a hydraulic function is the jumping spider , in which blood forced into the legs under pressure causes them to straighten for a powerful jump, without the need for bulky muscular legs. Hemoglobin is the principal determinant of the color of blood ( hemochrome ). Each molecule has four heme groups, and their interaction with various molecules alters

2128-415: The eukaryotes , the functional analogue of an organ is known as an organelle . In plants, there are three main organs. The number of organs in any organism depends on the definition used. There are approxiamately 79 Organs in the human body,but it is something that is debated as not all scientist agree on what counts as an organ. Except for placozoans , multicellular animals including humans have

2204-406: The five Chinese traditional elements and with yin and yang , as follows: The Chinese associated the five elements with the five planets (Jupiter, Mars, Venus, Saturn, and Mercury) similar to the way the classical planets were associated with different metals. The yin and yang distinction approximates the modern notion of solid and hollow organs. Blood Blood is a body fluid in

2280-418: The haruspices or the augurs in order to divine the future by their shape, dimensions or other factors. This practice remains an important ritual in some remote, tribal societies. The term "visceral" is contrasted with the term " parietal ", meaning "of or relating to the wall of a body part, organ or cavity " The two terms are often used in describing a membrane or piece of connective tissue, referring to

2356-399: The long arms of chromosomes 5 and 15 , respectively. A loss of function mutation of NKCC2 produces Bartter syndrome , an autosomal recessive disorder characterized by hypokalemic metabolic alkalosis with normal to low blood pressure. The energy required to move solutes across the cell membrane is provided by the electrochemical gradient of sodium. Sodium's electrochemical gradient

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2432-449: The nerves that innervate the parenchyma, the blood vessels that oxygenate and nourish it and carry away its metabolic wastes, and the connective tissues that provide a suitable place for it to be situated and anchored. The main tissues that make up an organ tend to have common embryologic origins, such as arising from the same germ layer . Organs exist in most multicellular organisms . In single-celled organisms such as members of

2508-482: The pulmonary veins . Blood then enters the left ventricle to be circulated again. Arterial blood carries oxygen from inhaled air to all of the cells of the body, and venous blood carries carbon dioxide, a waste product of metabolism by cells , to the lungs to be exhaled. However, one exception includes pulmonary arteries, which contain the most deoxygenated blood in the body, while the pulmonary veins contain oxygenated blood. Additional return flow may be generated by

2584-417: The stomach , intestines , gallbladder , bladder , and rectum . In the thoracic cavity , the heart is a hollow, muscular organ. Splanchnology is the study of the viscera. The term "visceral" is contrasted with the term " parietal ", meaning "of or relating to the wall of a body part, organ or cavity ". The two terms are often used in describing a membrane or piece of connective tissue, referring to

2660-401: The thick ascending limb of the loop of Henle and the macula densa in nephrons , the basic functional units of the kidney . Within these cells, NKCC2 resides in the apical membrane abutting the nephron's lumen , which is the hollow space containing urine . It thus serves both in sodium absorption and in tubuloglomerular feedback . The thick ascending limb of the loop of Henle begins at

2736-479: The urine . About 98.5% of the oxygen in a sample of arterial blood in a healthy human breathing air at sea-level pressure is chemically combined with the hemoglobin . About 1.5% is physically dissolved in the other blood liquids and not connected to hemoglobin. The hemoglobin molecule is the primary transporter of oxygen in mammals and many other species. Hemoglobin has an oxygen binding capacity between 1.36 and 1.40 ml O 2 per gram hemoglobin, which increases

2812-461: The 20th century, organ transplants began to take place as scientists knew more about the anatomy of organs. These came later in time as procedures were often dangerous and difficult. Both the source and method of obtaining the organ to transplant are major ethical issues to consider, and because organs as resources for transplant are always more limited than demand for them, various notions of justice, including distributive justice , are developed in

2888-516: The CO 2 bound to hemoglobin does not bind to the same site as oxygen. Instead, it combines with the N-terminal groups on the four globin chains. However, because of allosteric effects on the hemoglobin molecule, the binding of CO 2 decreases the amount of oxygen that is bound for a given partial pressure of oxygen. The decreased binding to carbon dioxide in the blood due to increased oxygen levels

2964-464: The NKCC2 cotransporter and consequently increases tubular flow rate which enhances potassium secretion and emphasises the hypokalaemic effect. Impaired sodium reabsorption increases diuresis by three mechanisms: Loop diuretics therefore ultimately result in decreased blood pressure. The hormone vasopressin also stimulates the activity of NKCC2. Vasopressin stimulates sodium chloride reabsorption in

3040-441: The acquisition of new functional properties by these tissues, and novel interactions of distinct tissue types. The study of plant organs is covered in plant morphology . Organs of plants can be divided into vegetative and reproductive. Vegetative plant organs include roots , stems , and leaves . The reproductive organs are variable. In flowering plants , they are represented by the flower , seed and fruit . In conifers ,

3116-483: The actual color of the venous blood. Skinks in the genus Prasinohaema have green blood due to a buildup of the waste product biliverdin . Substances other than oxygen can bind to hemoglobin; in some cases, this can cause irreversible damage to the body. Carbon monoxide, for example, is extremely dangerous when carried to the blood via the lungs by inhalation, because carbon monoxide irreversibly binds to hemoglobin to form carboxyhemoglobin, so that less hemoglobin

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3192-418: The blood into the cell. Other transporters assist in the movement of these solutes out of the cell through its apical surface. The end result is that solutes from the blood, particularly chloride, are secreted into the lumen of these exocrine glands, increasing the luminal concentration of solutes and causing water to be secreted by osmosis . In addition to exocrine glands, NKCC1 is necessary for establishing

3268-473: The blood or bound to plasma proteins), and removes waste products, such as carbon dioxide , urea , and lactic acid . Other important components include: The term serum refers to plasma from which the clotting proteins have been removed. Most of the proteins remaining are albumin and immunoglobulins . Blood pH is regulated to stay within the narrow range of 7.35 to 7.45, making it slightly basic (compensation). Extra-cellular fluid in blood that has

3344-475: The body, including: Blood accounts for 7% of the human body weight, with an average density around 1060 kg/m , very close to pure water's density of 1000 kg/m . The average adult has a blood volume of roughly 5 litres (11 US pt) or 1.3 gallons, which is composed of plasma and formed elements . The formed elements are the two types of blood cell or corpuscle – the red blood cells , (erythrocytes) and white blood cells (leukocytes), and

3420-422: The cell fragments called platelets that are involved in clotting. By volume, the red blood cells constitute about 45% of whole blood, the plasma about 54.3%, and white cells about 0.7%. Whole blood (plasma and cells) exhibits non-Newtonian fluid dynamics . One microliter of blood contains: 45 ± 7 (38–52%) for males 42 ± 5 (37–47%) for females Oxygenated: 98–99% Deoxygenated: 75% About 55% of blood

3496-462: The cell, thereby depolarizing it. Put another way, increasing internal chloride concentration increases the reversal potential for chloride, given by the Nernst equation . Later in development expression of NKCC1 is reduced, while expression of a KCC2 K-Cl cotransporter increased, thus bringing internal chloride concentration in neurons down to adult values. NKCC2 is specifically found in cells of

3572-412: The deeper portion of the renal outer medulla. Here, the urine has a relatively high concentration of sodium. As urine moves towards the more superficial portion of the thick ascending limb, NKCC2 is the major transport protein by which sodium is reabsorbed from the urine. This outward movement of sodium and the lack of water permeability in the thick ascending limb, creates a more diluted urine. According to

3648-413: The digestive tract. After severe acute blood loss, liquid preparations, generically known as plasma expanders, can be given intravenously, either solutions of salts (NaCl, KCl, CaCl 2 etc.) at physiological concentrations, or colloidal solutions, such as dextrans, human serum albumin , or fresh frozen plasma. In these emergency situations, a plasma expander is a more effective life-saving procedure than

3724-402: The ethical analysis. This situation continues as long as transplantation relies upon organ donors rather than technological innovation, testing, and industrial manufacturing. The English word "organ" dates back to the twelfth century and refers to any musical instrument. By the late 14th century, the musical term's meaning had narrowed to refer specifically to the keyboard-based instrument . At

3800-431: The exact color. Arterial blood and capillary blood are bright red, as oxygen imparts a strong red color to the heme group. Deoxygenated blood is a darker shade of red; this is present in veins, and can be seen during blood donation and when venous blood samples are taken. This is because the spectrum of light absorbed by hemoglobin differs between the oxygenated and deoxygenated states. Blood in carbon monoxide poisoning

3876-401: The execution of a specific body function form an organ system, also called a biological system or body system. An organ's tissues can be broadly categorized as parenchyma , the functional tissue, and stroma , the structural tissue with supportive, connective, or ancillary functions. For example, the gland 's tissue that makes the hormones is the parenchyma , whereas the stroma includes

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3952-468: The liver and heart evolved in the chordates about 550-500 million years ago, while the gut and brain are even more ancient, arising in the ancestor of vertebrates, insects, molluscs, and worms about 700–650 million years ago. Given the ancient origin of most vertebrate organs, researchers have looked for model systems, where organs have evolved more recently, and ideally have evolved multiple times independently. An outstanding model for this kind of research

4028-530: The lungs is still roughly 75% (70 to 78%) saturated. Increased oxygen consumption during sustained exercise reduces the oxygen saturation of venous blood, which can reach less than 15% in a trained athlete; although breathing rate and blood flow increase to compensate, oxygen saturation in arterial blood can drop to 95% or less under these conditions. Oxygen saturation this low is considered dangerous in an individual at rest (for instance, during surgery under anesthesia). Sustained hypoxia (oxygenation less than 90%),

4104-447: The more superficial portion of the thick ascending limb and the macula densa, and it has the highest affinity for sodium. This permits NKCC2B to function in this sodium-depleted environment without saturating. The NKCC2A isoform shows an intermediate distribution and affinity for sodium. In this way, NKCC2 is able to function properly along the range of sodium concentrations found along the thick ascending limb. Organ (anatomy) In

4180-407: The movement of skeletal muscles , which can compress veins and push blood through the valves in veins toward the right atrium . The blood circulation was famously described by William Harvey in 1628. In vertebrates, the various cells of blood are made in the bone marrow in a process called hematopoiesis , which includes erythropoiesis , the production of red blood cells; and myelopoiesis ,

4256-467: The new generation of plants (see clonal colony ). Many societies have a system for organ donation , in which a living or deceased donor's organ are transplanted into a person with a failing organ. The transplantation of larger solid organs often requires immunosuppression to prevent organ rejection or graft-versus-host disease . There is considerable interest throughout the world in creating laboratory-grown or artificial organs . Beginning in

4332-464: The observation of blood clotting in a transparent container. When blood is drawn in a glass container and left undisturbed for about an hour, four different layers can be seen. A dark clot forms at the bottom (the "black bile"). Above the clot is a layer of red blood cells (the "blood"). Above this is a whitish layer of white blood cells (the "phlegm"). The top layer is clear yellow serum (the "yellow bile"). In general, Greek thinkers believed that blood

4408-403: The opposing sides. Aristotle used the word frequently in his philosophy, both to describe the organs of plants or animals (e.g. the roots of a tree, the heart or liver of an animal) because, in ancient Greek, the word ' organon ' means 'tool', and Aristotle believed that the organs of the body were tools for us by means of which we can do things. For similar reasons, his logical works, taken as

4484-406: The opposing sides. The organ level of organisation in animals can be first detected in flatworms and the more derived phyla , i.e. the bilaterians . The less-advanced taxa (i.e. Placozoa , Porifera , Ctenophora and Cnidaria ) do not show consolidation of their tissues into organs. More complex animals are composed of different organs, which have evolved over time. For example,

4560-514: The organ that bears the reproductive structures is called a cone . In other divisions ( phyla ) of plants, the reproductive organs are called strobili , in Lycopodiophyta , or simply gametophores in mosses . Common organ system designations in plants include the differentiation of shoot and root. All parts of the plant above ground (in non- epiphytes ), including the functionally distinct leaf and flower organs, may be classified together as

4636-419: The oxygen is consumed; afterwards, venules and veins carry deoxygenated blood back to the heart. Under normal conditions in adult humans at rest, hemoglobin in blood leaving the lungs is about 98–99% saturated with oxygen , achieving an oxygen delivery between 950 and 1150 ml/min to the body. In a healthy adult at rest, oxygen consumption is approximately 200–250 ml/min, and deoxygenated blood returning to

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4712-509: The potassium-rich endolymph that bathes part of the cochlea , an organ necessary for hearing. Inhibition of NKCC1, as with furosemide or other loop diuretics , can result in deafness . NKCC1 is also expressed in many regions of the brain during early development, but not in adulthood. This change in NKCC1 presence seems to be responsible for altering responses to the neurotransmitters GABA and glycine from excitatory to inhibitory, which

4788-505: The production of white blood cells and platelets. During childhood, almost every human bone produces red blood cells; as adults, red blood cell production is limited to the larger bones: the bodies of the vertebrae, the breastbone (sternum), the ribcage, the pelvic bones, and the bones of the upper arms and legs. In addition, during childhood, the thymus gland, found in the mediastinum , is an important source of T lymphocytes . The proteinaceous component of blood (including clotting proteins)

4864-409: The protein transporter is still maintained. NKCC1 is widely distributed throughout the body, especially in organs that secrete fluids, called exocrine glands . In cells of these organs, NKCC1 is commonly found in the basolateral membrane , the part of the cell membrane closest to the blood vessels . Its basolateral location gives NKCC1 the ability to transport sodium, potassium, and chloride from

4940-413: The relationship between the muscular and skeletal systems . In the study of anatomy , viscera ( sg. : viscus ) refers to the internal organs of the abdominal , thoracic , and pelvic cavities . The abdominal organs may be classified as solid organs or hollow organs . The solid organs are the liver , pancreas , spleen , kidneys , and adrenal glands . The hollow organs of the abdomen are

5016-489: The same time, a second meaning arose, in reference to a "body part adapted to a certain function". Plant organs are made from tissue composed of different types of tissue. The three tissue types are ground, vascular, and dermal. When three or more organs are present, it is called an organ system. The adjective visceral , also splanchnic , is used for anything pertaining to the internal organs. Historically, viscera of animals were examined by Roman pagan priests like

5092-422: The second and the third most supplied organs, with 1100 ml/min and ~700 ml/min, respectively. Relative rates of blood flow per 100 g of tissue are different, with kidney, adrenal gland and thyroid being the first, second and third most supplied tissues, respectively. The restriction of blood flow can also be used in specialized tissues to cause engorgement, resulting in an erection of that tissue; examples are

5168-409: The shoot organ system. The vegetative organs are essential for maintaining the life of a plant. While there can be 11 organ systems in animals, there are far fewer in plants, where some perform the vital functions, such as photosynthesis , while the reproductive organs are essential in reproduction . However, if there is asexual vegetative reproduction , the vegetative organs are those that create

5244-461: The stoichiometry outlined above, each sodium ion reabsorbed brings one potassium ion and two chloride ions. Sodium goes on to be reabsorbed into the blood , where it contributes to the maintenance of blood pressure . Furosemide and other loop diuretics inhibit the activity of NKCC2, thereby impairing sodium reabsorption in the thick ascending limb of the loop of Henle. The action of these loop diuretics also reduces potassium reabsorption through

5320-489: The surface (e.g., during warm weather or strenuous exercise) causes warmer skin, resulting in faster heat loss. In contrast, when the external temperature is low, blood flow to the extremities and surface of the skin is reduced and to prevent heat loss and is circulated to the important organs of the body, preferentially. Rate of blood flow varies greatly between different organs. Liver has the most abundant blood supply with an approximate flow of 1350 ml/min. Kidney and brain are

5396-405: The thick ascending limb and they have different affinity for sodium that correlates with its localization. The isoform F is more predominant in the deeper portion of the thick ascending limb, where the sodium concentration is very high. NKCC2F is the isoform with the lowest affinity for sodium and this allows the cotransporter to work at this sodium rich environment. Conversely, NKCC2B is expressed at

5472-467: The thick ascending limb of the nephron by activating signaling pathways. Vasopressin increases the traffic of NKCC2 to the membrane and phosphorylates some serine and threonine sites on the cytoplasmic N-terminal of the NKCC2 located in the membrane, increasing its activity. Increased NKCC2 activity aids in water reabsorption in the collecting duct through aquaporin 2 channels by creating a hypo-osmotic filtrate. NKCC1 and NKCC2 are encoded by genes on

5548-443: The total blood oxygen capacity seventyfold, compared to if oxygen solely were carried by its solubility of 0.03 ml O 2 per liter blood per mm Hg partial pressure of oxygen (about 100 mm Hg in arteries). With the exception of pulmonary and umbilical arteries and their corresponding veins, arteries carry oxygenated blood away from the heart and deliver it to the body via arterioles and capillaries , where

5624-492: Was discovered in the year 1900 by Karl Landsteiner . Jan Janský is credited with the first classification of blood into the four types (A, B, AB, and O) in 1907, which remains in use today. In 1907 the first blood transfusion was performed that used the ABO system to predict compatibility. The first non-direct transfusion was performed on 27 March 1914. The Rhesus factor was discovered in 1937. Due to its importance to life, blood

5700-464: Was made from food. Plato and Aristotle are two important sources of evidence for this view, but it dates back to Homer's Iliad . Plato thinks that fire in our bellies transform food into blood. Plato believes that the movements of air in the body as we exhale and inhale carry the fire as it transforms our food into blood. Aristotle believed that food is concocted into blood in the heart and transformed into our body's matter. The ABO blood group system

5776-487: Was suggested to be important for early neuronal development. As long as NKCC1 transporters are predominantly active, internal chloride concentrations in neurons is raised in comparison with mature chloride concentrations, which is important for GABA and glycine responses, as respective ligand-gated anion channels are permeable to chloride. With higher internal chloride concentrations, outward driving force for this ions increases, and thus channel opening leads to chloride leaving

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