Cell yog ib chav tsev ntawm txhua lub neej ntawm peb lub ntiaj teb thiab qhib qhov system. Qhov no txhais tau tias nws lub neej yuav tsum muaj kev sib pauv tas li ntawm cov teeb meem thiab lub zog nrog ib puag ncig. Qhov kev pauv no yog nqa tawm los ntawm daim nyias nyias - lub ntsiab ciam teb ntawm tes, uas yog tsim los khaws nws txoj kev ncaj ncees. Nws yog los ntawm daim nyias nyias uas cellular metabolism yog nqa tawm thiab nws mus rau ntawm lub concentration gradient ntawm ib yam khoom, los yog tawm tsam nws. Kev thauj mus los thoob plaws cytoplasmic daim nyias nyias yog txheej txheem nyuaj thiab siv zog ntau.
Membrane - barrier thiab rooj vag
Cov cytoplasmic membrane yog ib feem ntawm ntau cov cell organelles, plastids thiab inclusions. Kev tshawb fawb niaj hnub no yog ua raws li cov kua dej mosaic qauv ntawm cov qauv membrane. Kev thauj mus los ntawm cov khoom hla ntawm daim nyias nyias yog ua tau vim nwslub tsev tshwj xeeb. Lub hauv paus ntawm daim nyias nyias yog tsim los ntawm lipid bilayer - feem ntau yog phospholipids txheej txheem raws li lawv cov khoom siv hydrophilic-hydrophobic. Cov khoom tseem ceeb ntawm lipid bilayer yog fluidity (lub peev xwm rau embed thiab poob qhov chaw), nws tus kheej sib dhos, thiab asymmetry. Qhov thib ob feem ntawm daim nyias nyias yog cov proteins. Lawv cov dej num muaj ntau haiv neeg: kev thauj mus los, txais tos, fermentation, paub.
Cov protein nyob hauv ob qho tib si ntawm daim nyias nyias thiab sab hauv, thiab qee qhov nkag mus rau nws ntau zaus. Cov cuab yeej ntawm cov protein nyob hauv daim nyias nyias yog lub peev xwm txav los ntawm ib sab ntawm daim nyias nyias mus rau lwm qhov ("flip-flop" dhia). Thiab qhov kawg tivthaiv yog saccharide thiab polysaccharide chains ntawm carbohydrates nyob rau saum npoo ntawm daim nyias nyias. Lawv txoj haujlwm tseem muaj teeb meem niaj hnub no.
Hom kev thauj khoom ntawm cov khoom hla ntawm daim nyias nyias
Active yuav yog xws li ib tug hloov ntawm cov tshuaj los ntawm lub cell membrane, uas yog tswj, tshwm sim nrog lub zog nqi thiab mus tiv thaiv lub concentration gradient (cov tshuaj yog pauv los ntawm ib cheeb tsam ntawm tsawg concentration mus rau thaj tsam ntawm siab concentration). Nyob ntawm seb lub zog twg siv, hom kev thauj mus los hauv qab no txawv:
- Primary active (lub zog - hydrolysis ntawm adenosine triphosphoric acid ATP rau adenosine diphosphoric acid ADP).
- Secondary active (muab nrog lub zog thib ob tsim los ntawm cov txheej txheem ntawm kev thauj khoom thawj zaug).
YProteins-pab
Nyob rau hauv thawj thiab thib ob, kev thauj mus los yog tsis yooj yim sua yam tsis muaj cov cab kuj. Cov protein thauj no yog qhov tshwj xeeb thiab tsim los nqa qee yam molecules, thiab qee zaum txawm tias qee hom molecules. Qhov no tau ua pov thawj sim ntawm cov kab mob hloov pauv, uas ua rau tsis muaj peev xwm ntawm kev thauj mus los thoob plaws daim nyias nyias ntawm qee yam carbohydrate. Transmembrane transporter proteins tuaj yeem ua tus kheej thauj khoom (lawv cuam tshuam nrog cov molecules thiab ncaj qha nqa lawv hla daim nyias nyias) lossis channel-forming (daim pores hauv daim nyias nyias uas qhib rau cov khoom tshwj xeeb).
sodium thiab poov tshuaj twj tso kua mis
Qhov piv txwv kawm tshaj plaws ntawm kev thauj khoom tseem ceeb ntawm cov khoom hla ntawm daim nyias nyias yog Na + -, K + -pump. Cov txheej txheem no ua kom ntseeg tau qhov sib txawv ntawm qhov sib txawv ntawm Na + thiab K + ions ntawm ob sab ntawm daim nyias nyias, uas yog qhov tsim nyog los tswj lub siab osmotic hauv cell thiab lwm yam txheej txheem metabolic. Lub transmembrane carrier protein, sodium-potassium ATPase, muaj peb ntu:
- Ntawm sab nraud ntawm daim nyias nyias muaj ob lub receptors rau cov poov tshuaj ions.
- Muaj peb cov sodium ion receptors nyob rau sab hauv ntawm daim nyias nyias.
- Cov sab hauv ntawm cov protein muaj cov haujlwm ATP.
Thaum ob lub poov tshuaj ions thiab peb sodium ions khi rau cov protein receptors ntawm ob sab ntawm daim nyias nyias, ATP kev ua haujlwm tau qhib. ATP molecule yog hydrolyzed rau ADP nrog kev tso tawm ntawm lub zog, uas yog siv rau kev thauj cov poov tshuaj ions.sab hauv, thiab sodium ions sab nraum lub cytoplasmic membrane. Nws yog kwv yees tias qhov ua tau zoo ntawm lub twj tso kua mis yog ntau tshaj 90%, uas nyob rau hauv nws tus kheej yog amazing heev.
Rau siv: Kev ua haujlwm ntawm lub tshuab hluav taws xob sab hauv yog li 40%, hluav taws xob - txog li 80%. Interestingly, lub twj tso kua mis kuj tseem ua hauj lwm nyob rau hauv lub opposite kev taw qhia thiab pab raws li ib tug phosphate pub rau ATP synthesis. Rau qee lub hlwb (piv txwv li, neurons), txog li 70% ntawm tag nrho cov zog yog siv los tshem tawm sodium los ntawm lub xov tooj ntawm tes thiab siv cov poov tshuaj ions rau hauv nws. Cov twj tso kua mis rau calcium, chlorine, hydrogen thiab lwm yam cations (ions nrog tus nqi zoo) ua haujlwm ntawm tib lub hauv paus ntsiab lus ntawm kev thauj mus los. Tsis muaj cov twj zoo li no tau pom rau anions (tsis zoo them ions).
Kev thauj mus los ntawm carbohydrates thiab amino acids
Ib qho piv txwv ntawm kev thauj mus los theem nrab yog kev hloov cov piam thaj, amino acids, iodine, hlau thiab uric acid rau hauv cov hlwb. Raws li qhov tshwm sim ntawm kev ua haujlwm ntawm lub twj tso kua mis poov tshuaj-sodium, ib qho gradient ntawm sodium concentrations yog tsim: cov concentration siab sab nraud, thiab qis sab hauv (qee zaum 10-20 zaug). Sodium nyiam diffuse mus rau hauv lub cell thiab lub zog ntawm no diffusion tuaj yeem siv los thauj cov khoom tawm. Cov txheej txheem no yog hu ua cotransport los yog ua ke nrog kev thauj mus los. Nyob rau hauv cov ntaub ntawv no, cov cab kuj protein muaj ob receptor chaw nyob rau sab nraud: ib tug rau sodium thiab lwm yam rau lub caij raug thauj. Tsuas yog tom qab ua kom ob leeg receptors, cov protein tau hloov pauv, thiab lub zog diffusion.sodium qhia cov khoom thauj mus rau hauv lub cell tiv thaiv cov concentration gradient.
Tus nqi ntawm kev thauj mus los rau lub cell
Yog hais tias ib txwm muaj kev sib kis ntawm cov tshuaj los ntawm daim nyias nyias mus rau lub sijhawm ntev, lawv cov concentrations sab nraud thiab sab hauv ntawm tes yuav sib npaug. Thiab qhov no yog kev tuag rau cov hlwb. Tom qab tag nrho, tag nrho cov txheej txheem biochemical yuav tsum tau ua nyob rau hauv ib puag ncig ntawm hluav taws xob muaj peev xwm sib txawv. Yog tsis muaj active, tiv thaiv ib tug concentration gradient, thauj cov khoom, neurons yuav tsis muaj peev xwm kis tau ib tug paj hlwb impulse. Thiab cov leeg nqaij yuav poob lub peev xwm los cog lus. Lub cell yuav tsis muaj peev xwm tswj tau osmotic siab thiab yuav vau. Thiab cov khoom ntawm cov metabolism yuav tsis raug coj tawm. Thiab cov tshuaj hormones yuav tsis nkag mus rau hauv cov hlab ntsha. Tom qab tag nrho, txawm tias amoeba siv lub zog thiab tsim kom muaj qhov sib txawv ntawm nws daim nyias nyias siv tib lub twj tso kua mis ion.
