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The sodium–potassium pump, a critical enzyme for regulating sodium and potassium levels in cells. Sodium ions (Na +) are necessary in small amounts for some types of plants, [1] but sodium as a nutrient is more generally needed in larger amounts [1] by animals, due to their use of it for generation of nerve impulses and for maintenance of electrolyte balance and fluid balance.
The concentrations of ions such as sodium and potassium in the cytosol are different to those in the extracellular fluid; these differences in ion levels are important in processes such as osmoregulation, cell signaling, and the generation of action potentials in excitable cells such as endocrine, nerve and muscle cells.
The sodium–potassium pump (sodium–potassium adenosine triphosphatase, also known as Na + /K +-ATPase, Na + /K + pump, or sodium–potassium ATPase) is an enzyme (an electrogenic transmembrane ATPase) found in the membrane of all animal cells. It performs several functions in cell physiology. The Na + /K +-ATPase enzyme is active (i.e. it ...
Sodium reacts with alcohols and gives alkoxides, and when sodium is dissolved in ammonia solution, it can be used to reduce alkynes to trans-alkenes. [75] [76] Lasers emitting light at the sodium D line are used to create artificial laser guide stars that assist in the adaptive optics for land-based visible-light telescopes. [77]
The main elements that comprise the human body (including water) can be summarized as CHNOPS. Element Symbol percent mass percent atoms Oxygen O 65.0 24.0 Carbon C 18.5 12.0 Hydrogen H 9.5 62.0 Nitrogen N 2.6 1.1 Calcium Ca 1.3 0.22 Phosphorus P 0.6 0.22 Sulfur S 0.3 0.038 Potassium K 0.2 0.03 Sodium Na 0.2 0.037 Chlorine Cl 0.2 0.024 Magnesium Mg
Metabolism (/ m ə ˈ t æ b ə l ɪ z ə m /, from Greek: μεταβολή metabolē, "change") is the set of life-sustaining chemical reactions in organisms.The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the conversion of food to building blocks of proteins, lipids, nucleic acids, and some carbohydrates; and the ...
The sodium-calcium exchanger (often denoted Na + /Ca 2+ exchanger, exchange protein, or NCX) is an antiporter membrane protein that removes calcium from cells. It uses the energy that is stored in the electrochemical gradient of sodium (Na +) by allowing Na + to flow down its gradient across the plasma membrane in exchange for the countertransport of calcium ions (Ca 2+).
The biological half-life (the average time it takes for the human body to eliminate half the amount in the body) for uranium is about 15 days. [3] Uranium's radioactivity can present health and environmental issues in the case of nuclear waste produced by nuclear power plants or weapons manufacturing.