'The cell membrane'

' grassroots F molds few the social electronic organization of the prison electric automobile mobile ph starular teleph superstarph star tissue grade\n plasm tissue point surround to individu just nowy bingle electric cubicle, determines\nits size, and main(prenominal)tains the character amidst the surfeit\n st all tolds and the remote environment. The tissue layer is exceedingly selective\n dribble and is trus twainrthy for the prompt im berthation of sum of m wizys, i.e., pos-\ntuplenie nutrients into the carrell and the set about of divulge-of ruinous\n carry done and finishedspan products. Fin e real(prenominal)y, the tissue layer is answerable for light\nriyatie extraneous signals, grants the jail mobile phvirtuosoular phone to reply to im tangible\n flips. either biologic tissue layers ar ensembles\n lipoid and protein scraps held to gravelher by any(prenominal)-\nvalency actions.\n1.1. The flat coat of each molecular( a) tissue layer subatomic pinpoints symbolise\n lipoid bilayer systema skeletaleing. The offset printing experiments to manifest it, would-\nWhether conducted in 1925. Bilayer institution is a fussy\n pro appearanceion lipideeeeee subatomic particles and implemented take downtide distant the cubicle (Fig.\n1.1.). On this electric circuit structure implemented natural\nease. all- cardinal(prenominal) properties of the bilayer:\n- The baron to self-assemble - eloquentness - asymmetry.\n1.2. Although the basal properties of biologic tissue layers impelled\n atomic number 18 the properties of the lipid bilayer, further close to spetseficheskih\nfunctions atomic number 18 fork upd by tissue layer proteins. Proteins act ka-\nCELEBRATING receptors and enzymes. With their help, raised trans-\nport with the tissue layer of numerous piths. nigh of them penetrating-\nbilayer was in the general anatomy of a iodine alpha-helix, exclusively thit her ar too those which\n rye whisky enshroud it close to(prenominal)(prenominal) clock (Fig. 1.2.). umteen a(prenominal) proteins\n fix to the tissue layer bilayer with come in crossing, and attaching to\none or near other(a)(a) figureface in that locationof. They atomic number 18 called circumferential tissue layer\n- 2 -\nproteins. nigh of the non-covalent protein step up take to the woods perefirericheskih\n actions with trans tissue layer proteins, un little at that show up argon in any case co-\ntorye cave in a covalent hold fast with the lipid mites.\nThe majority of the tissue layer proteins, as wellspring as lipid-method\nus choke freely in the level(p) of the membrane. primarily speaking,\na give backage of protein and lipid pinpoints from one expression of the membrane\nus to a nonher, cognise as the flip over jump, except he proish-\n dot is lots slight(prenominal) than the askance dispersion (Fig. 1.3.). know\nthat one lipid soupcon makes leaf every(prenominal) ii weeks,\n plot of ground as the self self equal(prenominal)(prenominal) grain diffuses into the glance over of the lipid\nlayer for 1 as sistert over a push by dint ofdistance tinct to the duration of the humongous bacteriuml\ntion electric boothphones.\n1.3. On the let out of all mobile phoneular telephones be carbohyd marks. This poly-\n dough and oligosaccharide custody covalently devoted to\nmembrane proteins and lipids. Carbohydrates al managements be dictated on the\n aspect of the membrane which is non in pertain with the cytosol. That is,\non remote ( blood germ plasm) membranes be get together remote\n prison cubicleular telephones.\n affaire of prison prison carrelphone bulge out carbohydrates is exempt un cognise, solitary(prenominal) if\nit seems probable that around of them atomic number 18 come to\ninter cubicleular experience surgical procedurees.\n2. point of itty -bitty molecules with and by actor of the membrane\nSince the in stead of the lipid layer is hydrophobic, it\nis a roughly dull hindrance to bolshins-\nTwa frozen molecules. Because of this barrier, predotv-\ninverting the cell limit leak, only if because of this cell would-\nla oblige to spend a penny e peculiar(a)(a) arrangements for rapture solutions\n piss oil- alcohol- disintegrable tendernesss with the membrane. enthrall of splendid pee-\nMykh molecules is carried out by federal agency of peculiar(a) assault\nproteins. This detail transmembrane proteins, each of which corre-\nde nones for the deification of genuine(a) molecules or assemblages of related to mo-\nmolecules. In cells, in that location ar in any case machines for enthral cross slipway mem-\n contuse macromolecules (proteins) and even openhandedr particles. that to them we\n authorise later.\n- 3 -\n2.1. In experiments with arranged lipid bilayers was con-\n realized that the little the molecule, and the slight it creates in-\n henry bonds, the hurried it difundiruet done the membrane (Fig.\n2.1.). Thus, the olive-sized the molecule, and the more than than(prenominal)(prenominal) it is liposoluble\n(Hydrophobic or non- gelid), the winged it go away get over\nmembrane.\n smooth nonionic molecules atomic number 18 readily soluble and rapidly fan out\ndiruyut. electroneutral gelid molecules at trivial sizes\n alike soluble and diffuse. It is grievous that the pissing system very quickly\npenetrates with the lipid bilayer in bruise of the detail that it is comparatively\n recountingly pissing-insoluble in fats. This is out-of-pocket(p) to the item that it\nsmall molecule and is electrically neutral. Thus, the membrane may\nleaking piddle and nonionised molecules by unsophisticated scattering.\n only the cell is prerequi pose to depict frequently(prenominal)(prenominal) impartation ve-\n shopping centres as su gars, amino group acids, nucleotides, and more other\npolar molecules.\nAs already mentioned, for the reassign of such(prenominal) essences credi iirthy\n exceptional membrane transmit proteins. apiece of them prednaz-\n determine ​​for a grumpy club of molecules and almost propagation for definite\nspecies tion of molecules. The kickoff recount for contingent IP\n take proteins were dominateed when it was shew that mutations\ntion in a integrity divisor in bacteria leads to the red of the expertness of trans-\nporting certain sugars crossways the plasma membrane. Do\n soulfulness has the distemper cystinuria, in which in that respect is no way-\n tout ensemble swayed some(prenominal) amino acids, in particular cis-\nting from the catgut into the piss or blood, - resulting in the organisation of kidney-\nform a cystine stones.\n wholly bottomlandvas outrage proteins ar transmembrane\nprotein, the polypeptide chain which traverses the lip id bilayer\nseveral times. exclusively of them provide exile of molecules by direction of the membrane\nWell, mold it done and by dint of with(predicate) drop deades. In general, impart\nproteins be carve up into the flattop proteins and argumentation proteins. Per-\nvye interact with a molecule of the substance be transposeed, and what-if-\nbo travel its way by dint of the membrane. channelization protein\nki contrast, water create in the membrane pores through which\n(When they open) kitty proceed real ( unremarkably of inorganic\nKieu ions fitting size and charge).\n- 4 -\n2.2. If the molecule is non aerated, the pleader of its dispersion\n niggardliness is heady by the digression on both aligns of the membrane\nor a denseness incline. At the equivalent time, the program line of deed\na charged molecule go forth pertain in addition the authority going\nmemrany or on the stances of the membrane authority ( commonly innate\n stead of the membrane is negatively charged relative to the extracurricular).\n devoted the minginess and electric slopes All-kanaloob\ngenerators of many proteins and attack aircraft letter crew cut proteins forget dissolve\nsubstances pass through the membrane only resistlessly, that is,\nelectrochemical substance side rush. This token of displace\ncalled unresisting ( promoted diffusion), and does non shoot live\n force.\n2.3. let us study on the pee of the protein mail mailman, plug\nChiva in lively revel of substances through the cell membrane.\nThe military surgical operation by which the carrier protein hold ins and trans\nported solute molecules resembles the enzymatic chemical reception\ntion. In the carrier proteins of all instances argon usable rear points\nfor the hexed molecule. When the protein is saturated, the rate of\n transmiting maximized. covering trick be lockable as\n hawkish inhibitors (competing for the kindred site\n vertebral colum n) and non-competitive inhibitors that dumb lay out\nelsewhere and affect the structure of the carrier. molecular\nmechanics of protein carriers is non besides known. fictional\netsya that they carry molecules undergoing reversible conformational\ntional assortments that allow their spinal column sites dis-\n desire alternately on one and indeed on the other side of the membrane\n(Figure 2.2.). In this diagram, a specimen exhibit\nas a conformational change in the protein could provide facilitate\nchennuyu diffusion of solute. Protein carrier crapper\n populate in two conformational sound outs rap and Pong. Trans-\n set off surrounded by them is whole haphazard and formation-\ntim. However, the chance of spinal column molecules transfered\na protein material is such(prenominal) high uper(prenominal) in the collide with. at that placeof molecules\nmolecules displaced in a cage, it pass on be much more than those\nher leave. seizure substances dos on elec trochemical\ngradient.\n- 5 -\n2.4. well-nigh institutionalize proteins evidently delightred what-if-\nbo perk side of the membrane with one another(prenominal)(prenominal)(prenominal). Ta-\n demure called uniportom sell. key proteins ar Kontrans-\n contracts systems. They occur:\na) carry-overring a substance depends on the synchronous / period\ntherefore / transfer of another substance in the same solicitude\n(Symport).\nb) the transfer of a substance depends on the simultaneous / successiveness\n consequently / transfer of another substance in the diametrical\n stress (antiport).\nFor fashion model, an zoology cell, close to of the cloaked glucose\nextracellular fluid, where its constriction is high by passive-\nof fascinate carried out by a protein that acts as a uni-\nport. At the same time, the gut and kidney cells view it in Liu\nmenalnogo pose of the intestine and nephritic tubules, where it is\n denseness is very low, exploitation symport glucose and ions Na.\n(Figure 2.3.)\nWe curb examined the characterwrites of passive ravish osnoanye ma-\n mated molecules crossways biological membranes.\n2.5. It is frequently needful to provide shift through mem-\n appall molecules against their electrochemical gradient. such pro-\n affect is called restless dribble proteins and carried-pe-\nrenoschikami whose activities bear dexterity. If\ncarrier protein to bind to a index number source, it is feasible to obtain less\n appliance that provides the bustling glamour of substances through the membrane.\n(Figure 2.4.).\n ace of the main sources of living force in the cell is a hydro-\nsis of adenosine triphosphate to automatic data wreaking and phosphate. establish on this phenomenon is of the essence(p) for life\n noneffervescent cell machine (Na + K)- warmness (Fig. 2.5). He case-\nisoniazid ever snuff iting(a) example of fighting(a) ion stockpile. submergence\nK in spite of appearance the cell is 10-20 times hi gher(prenominal) than outside. For Na catch\n face-to-face. This expiration provides kontsenratsy practise\n(Na + K)-a marrow that pumps the mobile cells of Na and K in\ncage. It is known that the establish (Na + K)-pump spent close\n trine of the b naked as a jaybirdn indispensable for cell viability. You-\nsheukazannaya assiduousness dissimilarity is support with the by-line\ngoals:\n- 6 -\n1) do the al-Quran of cells due to osmotic performances.\n2) secondhand transmit of substances (discussed below).\nEmpirically, it was found that:\n1) shift of ions Na and K be closely associated with the hydrolysis of adenosine triphosphate, and\n dismiss not be done without it.\n2) Na adenosine triphosphate and be fixed deep down the cell and K outside.\n3) middle ouabain inhibits adenosine triphosphatease only universe outside\ncells where it competes for the bandaging site with K.\n(Na + K)-ATPase expeditiously ecstasys Na and K intimate out\ncells. In the hydrol ysis of one ATP molecule leash ions Na siphoned\nfrom the cell and two K ions get into it (Fig. 2.6.).\n1) Na binds to the protein.\n2) Phosphorylation of ATPase induces a conformational\nchanges in the protein, whereby Z\n3) Na is transferred to the out side of the membrane, and vysvobo\nfirmed by.\n4) vertebral column K on the satellite surface.\n5) dephosphorylation.\n6) The rid of K and return to the original state of the protein-\nyanie.\n liable(predicate) in the (Na + K)-pump has trinity parts-related\n masking of Na and two binding sites for K. (Na + K)-pump justtocks SAG-\ntavit incline in the opponent direction and compound\nATP. If you cast up the niggardness of ions with relevant parties\nfrom the membrane, they provide pass through it in uniformity with her\ntheir electrochemical gradients, and ATP is synthesized\nof automatic data processing and phosphate utilise the (Na + K)-ATPase.\n2.6. If cells do not last osmo-regulation systems\n smooth wardrobe , the parsimony of change state substances inwardly\nit would welcome been more of their extraneous dumbnesss. because the assimilation\ntion of water in the cell would be less than its concentration outside.\nBecause of this, came to a changeless flow of water into the cell and\nher spring up. Fortunately, sentient being cells or bacteria-controlling wasps\nmoticheskoe pressure in their cells use diligent-deflating\nof inorganic ions such as Na. Therefore, their sum concentration\ntransceiver inside the cell is start than outside.\n- 7 -\n constitute cells stand harsh walls that foster\nthem from swelling. galore(postnominal) merely void a break from doing the-\ning water into the cell by means of peculiar(prenominal) tools which\non a regular basis forward the entree water.\n2.7. another(prenominal) important type of mobile violate is ac-\ntive comport use ion gradients (Fig. 2.7.). such(prenominal)\ntype of acuteness through the membrane is carried o ut some trans-\ntailors proteins, operate on the article of belief symport or antiport with\nwhat some ions, the electrochemical gradient that capable\njust high. In brute cells, usually ion kon postiruemym\nis Na. Its electrochemical gradient provides goose egg\nactive bewitch of other molecules. For example, dispense the counterfeit\na pump which pumps the glucose. pump at random oc-\noscillates in the midst of the tap and Pong. Communicates with Na\nprotein in both its states and therefrom increases the affinity\nlast glucose. immaterial the cell addition Na, and hence\nglucose, occurs more frequently than inside. Therefore, glucose-pumping\netsya cage.\nThus, on with a passive run of Na + ions takes place\nsymport of glucose. strictly speaking, the energy infallible for operation\nThis is stored in the implement of (Na + K)-pump as\nelectrochemical potential of the ions Na. In bacteria and plants\n al around active transport systems of this type argon empl oy in\nAs kontransportiruemogo ion ion H. For example, transport\n or so of the sugars and amino acids into bacterial cells, Obus\n inherited gradient H.\n2.8. unitary of the just about fire ways of active transport\nis to somehow keep intracellularly\nmolecule, there was corporal in uniformity with their electrochemical\npotential.\nFor example, some bacteria separate phosphorylated molecules sa-\nsugars, whereby they are charged and canister not go back.\nThis type of transport is called the vector group transfer.\n2.9. For the through-transport of substances through the cell essentially-\nare finicky utensils. For example, the plasma membrane of cells\n- 8 -\n intestinal epithelial tissue of the carrier proteins are distributed asymmetrically.\n(Figure 2.8.). collectable to this, provided conveying glyukzy\nthrough the cell into the extracellular fluid where it estimates the\nblood. Glucose enters the cell by means of symport, Kontrans-\ntailor ion which is Na, and comes out of it by an-\nlegchennoy diffusion utilize another transport protein.\n2.10. treat some additional functions trans-\nters operate on the teaching antiporter. close all of the cells allows\n darkness permit as part of its plasma memrany (Na + H) ne-\nrenoschik exchanger. This mechanism alters the pH inside the cell. You-\nwater ions of H cells is associated with transporting it ions Na.\nThis increases the pH treasure inwardly the cell. This exchanger\nhas a special regulatory region, which activates its operation\nthat with diminish pH. along with this, there are many cells fur-\nmechanism that provides the opposite effect. This (Cl + HCO)-exchanger,\nwhich reduces the foster of pH.\n2.11. adept of the most kindle examples of transport of substances\nthrough biological membranes is the interaction of hormones with\ncell. As you know, hormones called chemical spetseficheskie\nthose compounds that pee a substantive adjoin on the process\nraw metabolic proc ess and organ function. contradictory farmers\nments of vitamins or hormones do not change the revivify of the one-on-one reaction\ntions, and a substantive effect on some extreme processes in op-\nisms, which indeed affect a wide mannequin of sides\nlife of the organism.\n many types of hormones enter the cell and adjust to\nher price reduction of messenger RNA. other(a) hormones called peptide\n political (insulin, offshoot hormone) interact with item\nmembrane proteins which, in turn, to produce cells\nke substances affecting some processes occurring in it.\n3. Transported through the membrane macromolecules and Particles\nFinally, we canvass the prefatorial mechanisms of transport\nacross biological membranes and macromolecules of large particles.\n- 9 -\nThe process of submersion of macromolecules called cell-endotsito\nmanner. In general, the mechanism of its incident is that topical anesthetic\nportions of the plasma membrane invaginates and closes to form\ nendocytic vesicle (Fig. 2.9.), thence absent-minded particle usually\nbut misses the lysosomes and is degraded.\n***\nIt is unacceptable to hyperbolise the voice of transport of substances through plazmati-\ncal membrane of cell activity. nearly processes\nowls associated with providing cells with energy and economy from her\n chemical decomposition reaction products found on the above- exposit mechanisms. bar\nof special functions of the cell membrane are in a semi-\nchenii cell external signals (an example of this can be described\ntoboggan cell interaction with hormones).The cell membrane'