what is sodium potassium pump?how does it work?
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Na+/K+-ATPase (also known as the Na+/K+ pump or sodium-potassium pump) is an enzyme (EC 3.6.3.9) located in the plasma membrane (specifically an electrogenic transmembrane ATPase). It is found in the plasma membrane of virtually every human cell and is common to all cellular life. It helps maintain cell potential and regulate cellular volume.\n\nIn order to maintain the cell potential, cells must keep a low concentration of sodium ions and high levels of potassium ions within the cell (intracellular). Outside cells (extracellular), there are high concentrations of sodium and low concentrations of potassium, so diffusion occurs through ion channels in the plasma membrane. In order to keep the appropriate concentrations, the sodium-potassium pump pumps sodium out and potassium in through active transport.\n\nThe mechanism is:\n\nThe pump, with bound ATP, binds 3 intracellular Na+ ions. \nATP is hydrolyzed, leading to phosphorylation of the pump at a highly conserved aspartate residue and subsequent release of ADP. \nA conformational change in the pump exposes the Na+ ions to the outside. The phosphorylated form of the pump has a low affinity for sodium ions, so they are released. \nThe pump binds 2 extracellular K+ ions, leading to the dephosphorylation of the pump. \nATP binds, and the pump reorients to release potassium ions inside the cell so the pump is ready to go again. \n\nAs the plasma membrane is far less permeable to sodium than it is to potassium ions, an electric potential (negative intracellularly) is the eventual result.\n\nThe electrical and concentration gradient established by the sodium-potassium ATPase supports not only the cell resting potential but the action potentials of nerves and muscles. Export of sodium from the cell provides the driving force for several facilitated transporters, which import glucose, amino acids and other nutrients into the cell. Translocation of sodium from one side of an epithelium to the other side creates an osmotic gradient that drives the absorption of water.\n\nAnother important task of the Na+-K+ pump is to provide a Na+ gradient that is used by certain carrier processes. In the gut, for example, sodium is transported out of the resorbing cell on the blood side via the Na+-K+ pump, whereas, on the resorbing side, the Na+-Glucose symporter uses the created Na+ gradient as a source of energy to import both Na+ and Glucose, which is far more efficient than simple diffusion. Similar processes are located in the renal tubular system.
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salt helps maintain water in the body
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People with excessive potassium, medical term as hyperkalemia, are usually asymptomatic. Some may suffer from vague non-specific symptoms, such as vague symptoms nausea,  fatigue, muscle weakness, or tingling sensations. However, it is a potentially life-threatening illness that can lead to sudden death from cardiac arrhythmias and asystole in severe cases.\n\nHowever, except in uncommon conditions (e.g. direct intravenous potassium injection, rhabdomyosis, tumor lysis of lymphoma or other malignancy after chemotherapy), normal individual with NORMAL renal function (urine is the major source for potassium excretion) very rarely become hyperkalemic due to excessive ORAL intake. However, people with renal failure is restricted to limited amount of daily potassium intake.
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depolarization which stimulates adjacent Na+ and K+ gates to open, thus starting an action potential in the muscle cell
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The kidneys normally excrete excess potassium from the body. Therefore, most cases of hyperkalemia are caused by disorders that reduce the kidneys' ability to excrete potassium.\n\nThere are no at-home treatments I could find... you should really talk to your doctor about it.
926256
Normally, the soap we used is sodium or potassium salt made from the mixture of a sodium or potassium solution with fat acid.  Therefore, sodium palmitate, for example, is a salt and also a soap we used daily.  When sodium palmitate is dissolved by water, it will ionize into sodium ion and palmitate ion.  Palmitate ion is made out of two parts which is the hydrophobic part and the hydrophilic part.  The hydrophobic part will dissolves in grease or oil but not water, while the hydrophilic part will dissolve in water but not grease or oil.  In short, the hydrophobic part of the ion dislikes water while the hydrophilic part of the ion likes water.  Therefore, the hydrophilic part of the palmitate ion will dissolve in water, reducing or breaking the surface tension of water as the hydrophilic part of the ion forces itself into the neat structure of the water.  Therefore, the neat structure of the water will be broken up, causing the surface tension of water to break up.  For your information, palmitate ion is the one doing all the cleaning, breaking up the dirt on our clothes.  As for detergent, it ionizes into sulfonate ion and has two parts as well.  The mechanism of detergent breaking the surface tension of water is the same as the mechanism of soap.  I hope you understand what I’m saying as I learn all these in a different language.  Sorry if I wrote the wrong terms.
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Your heart has signals that travel to it telling it when to beat.  The things that signal are called nerves, which you probably know, but I am going to explain how I look at it.  The nerves have high  sodium (Na+) on the outside (making it positive).  On the inside of the nerve axon, there are high levels of potassium (K+) (making it negative).  The "inside" and "outside" are seperated by a membrane which has gates and channels that allow the K+ to move out and the Na+ to move in.  When the "charge" changes enough in the axon of the nerve, you get a signal sent "down the line".   If you are low in K+, the signals can't work right because enough K+ doesn't move in/Na+ doesn't move out to cause a signal or signals at the wrong time.  Your heart gets out of sync and things get all messed up, arrhythmias and such.
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The balanced solution is nothing else than a special physiological salt solution.  Near the sodium chloride it generally contains CaCl2, KCl, potassium and sodium-phosphate, Mg-salt(chloride or sulphate), sodium hidrocarbonate.\nAs additional component it may contains some glucose and/or phenol red as a pH indicator.
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Aldosterone is a hormone secreted directly by the adrenal gland and plays a big role in regulating sodium and potassium levels in the blood. Specifically, the hormone acts to increase sodium reabsorption in the blood. \n\nIn people who are deficient of aldosterone, there is less sodium reabsorption than normal. Since water follows salt, you can deduce that in people with low levels of aldosterone, they will have less blood flow and less blood pressure, which can be bad.
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It's usually only prescribed for people on diuretics for blood pressure. Potassium is so widespread in food that it is not needed as a mineral supplement. BTW, good natural sources of potassium are potatoes, bananas and orange or tomato juice.
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It's very similar to the nephron in the kidneys. Basically, the colon absorbs water along with sodium and can secret potassium if need be.
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The correct sequence is (B).  Here's a numbered explanation:\n\nUnder normal conditions, potassium ions leak out of a cell faster than sodium ions leak in; as a result, a 'resting' cell membrane will have a negative potential.  Some stimulus may then cause a depolarization (movement toward neutral potential) in some small part of the membrane [4] -- this is the beginning of the action potential process.  Depolarization allows sodium ions to flood through the cell membrane [6], driving the membrane into positive potential [7].  At a certain point, the sodium channels shut down in response to the change in potential [1], and the flood reverses -- now potassium ions diffuse out of the cell in larger numbers [2].  Eventually, the sodium channels reach their normal state again [3].  The potassium channels also calm down, but just like the sodium ions before, they've gone too far, resulting in hyperpolarization of the membrane (or what is also called the 'undershoot,' because the potential goes more negative than its resting value) [5].
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Cells have openings on their outer membrane - ion pumps. The pumps regulate the concentration of sodium and potassium ions in the cell. The difference in ions in and out of the cell creates an electric potential across the membrane allowing a nerve impulse to propagate along its length. Jens C. Skou won the 1997 Nobel Prize for work in this area. Several ion pumps have now ben described.
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There are potassium ion channel pumps on the cell membrane. This pump pumps out CL ions and bring in K+ ions. It  goes against the flow of diffusion, so energy is needed. When an action potential is created, it oppens Cl- gated channels which, due to the differnt concentrations (more on the outside) the CL rushes back in, creating a change in cell voltage.
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The neuron actively builds the ionic gradients by pumping specific ions into or out of the cell.  Na+ and K+ are the major players, Cl- less so, and Ca2+ the least important.  Na+ ions are pumped out and K+ ions are pumped in by the Na+/K+ ATPase.  At rest, there are a lot of Na+ ions outside the cell and a lot of K+ ions inside the cell.  The charge imbalance means the cell has an electrical voltage across its membrane.\n\nWhen the neuron is activated, it opens up ion channels that allow these ions to suddenly flow into or out of the cell down their gradients.  For example, Na+ ions are suddenly going to rush into the cell and K+ ions will rush out of the cell slightly later.  The result is a sudden change in the electrical voltage of the cell membrane.  This is the basis of how nerves generate electrical impulses.
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Nothing whatsoever to do with osmosis.\n\nThe neurons have specialised proteins embedded in the cell membrane. Those proteins act as tiny little pumps, pumping sodium out of the cell. That leads to a concentration gradient  with more positive ions outside the cell than inside. As a result potassium diffuses into the cell along that concentration gradient.\n\nOsmosis plays no role since nothing is moving against a concentration gradient.\n\n\nIt is the operation of those sodium pumps that makes nerves so very expensive to run. For the nerves to be operational those pumps have to run constantly, 24/7. And they burn energy the whole time. Hideously expensive. But we started down that path when we were still unicellular organisms and it is now impossible to reverse engineer the system to come up with a more cost effective solution that sees the nerves use energy only when they are required.
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An imbalance of the other major blood chemicals which are calcium, sodium and potassium.  If your potassium level is too low, your magnesium level can be elevated.  Potassium is available in potatoes and bananas.  Calcium is in milk and cheese and the small bones in tiny fish like sardines and anchovies.  Sodium is in salt.  They work together in your body and an imbalance in one can effect the absorption or elimination of the others.