Makamaka kapangidwe ndi ntchito ya nembanemba selo

Mu 1972 iye anali atapereka chiphunzitso kuti Kakhungu pang'ono permeable ozungulira selo ndi kukachita angapo ntchito yofunika kwambiri, kapangidwe ndi ntchito ya nembanemba selo nkhani yaikulu yokhudza uziyenda bwino maselo onse m'thupi. chiphunzitso Cell anakhala ambiri m'zaka za m'ma 17, ndi kuyambitsa kwa maso a. Iwo anamva kuti zomera ndi nyama zimakhala ndi lopangidwa ndi maselo, koma chifukwa cha otsika kusamvana kwa chipangizo kunali kosatheka kuona zopinga aliyense padziko maselo nyama. M'zaka za m'ma 20, chikhalidwe mankhwala Kakhungu anali ankafufuza mwatsatanetsatane, chinapezeka kuti maziko ake ndi lipids.

Kapangidwe ndi ntchito ya nembanemba selo

Selo nembanemba lozungulira cytoplasm maselo amoyo, mwathupi kulekanitsa zigawo okhudza maselo ambiri ku malo akunja. Bowa, tizilombo zomera komanso ndi selo mpanda amene amateteza ndi kuteteza Ndime ya mamolekyulu lalikulu. Cell zimagwira ntchito zosiyanasiyana komanso udindo mu mapangidwe cytoskeleton ndipo zaikidwa ndi extracellular masanjidwewo particles zina zofunika. Izi ndi zofunika kuti awasunge pamodzi kupanga zimakhala ndi ziwalo. Features ya kapangidwe selo nembanemba monga permeability. The Ntchito yaikulu ndi kuteteza. Kakhungu imakhala wosanjikiza phospholipid ndi mapuloteni ophatikizidwa. Mbali imeneyi kumatanthauza njira monga guluu wolimba selo, ion madutsidwe ndi machitidwe kusonyeza ndipo amakhala pamwamba ogwiritsa kwa nyumba zingapo extracellular, kuphatikizapo khoma glycocalyx ndi cytoskeleton mkati. Kakhungu nawonso lofotokozabe angathe maselo, ntchito monga fyuluta kusankha. Ndi kusankha permeable kuti ayoni ndi tizidutswa organic, asaaonerera kayendedwe ka particles.

zimagwirira Tizilombo zokhudza selo nembanemba

1. chabe mayamwidwe: ena zinthu (mamolekyulu yaing'ono, ayoni) monga mpweya woipa (CO2) ndi mpweya (O2), amatha kulowa madzi a m'magazi Kakhungu ndi mayamwidwe. Macitidwe casing monga malire kwa tinthu tina ndi ayoni, iwo akhoza anaikira mbali zonse.

2. transmembrane mapuloteni TV ndipo onyamula: zakudya monga shuga kapena kwa amino zidulo, ayenera kulowa khola, ndi mankhwala ena kagayidwe kachakudya muzisiyira izo.

3. endocytosis - ndi njira imene mamolekyulu ndi odzipereka. mapindikidwe pang'ono (intussusception) analengedwa mu madzi Kakhungu, momwe thunthu kwa kusamutsidwa, ndi kuwameza. Izi zimafuna mphamvu, ndipo motero, ndi mawonekedwe zoyendera yogwira.

4. Exocytosis: amapezeka m'selo yosiyana kuchotsa undigested zinthu zatsalira anabweretsa endocytosis kuti secrete zinthu, monga mahomoni, michere, ndi zinthu zoyendera njira yonse kupyola chotchinga selo.

kapangidwe maselo

Maselo - chipolopolo kwachilengedwenso wopangidwa makamaka a phospholipid ndi kulekanitsa zili maselo onse kwa chilengedwe. The ndondomeko ya mapangidwe kumachitika zokha m'mikhalidwe yachibadwa. Kuti timvetse ndondomeko imeneyi ndi bwino kufotokoza kapangidwe ndi ntchito ya nembanemba khungu, komanso katundu zofunika kuti aone chikhalidwe cha dongosolo phospholipid, ndilo khalidwe la kugawanika structural. Pamene phospholipids m'malo amadzimadzi cytoplasm kufika ndende yovuta, iwo amaphatikizidwa mu micelles, amene ali wolimba m'malo amadzimadzi.

katundu Kakhungu

• Kukhazikika. Izi zikutanthauza kuti pambuyo mapangidwe kugwa Kakhungu n'zokayikitsa.
• Mphamvu. The zamadzimadzi envelopu wangwiro zokwanira kuteteza Ndime ya zinthu kumalo ozizira, anapanga kudzera malire sangathe kupitirirapo ngati solutes (ayoni, shuga, amino zidulo), ndi tinthu wokulirapo (mapuloteni).
• Mphamvu zachilengedwe. Mwina chuma chofunika kwambiri, ngati tikambirana kapangidwe ka khungu. Selo nembanemba akhoza poyera kuti tizilombo ta osiyana, ndipo apangidwe zosinthira ndi ambike. Zifukwa zina, monga maphatikizidwe wa vesicles budding kapena akhoza kusweka, koma sichikupezeka. Firiji, zigawo zikuluzikulu zamadzimadzi ali mu zonse, wachisokonezo zoyenda, kupanga khola madzimadzi malire.

Madzimadzi zithunzi lachitsanzo

Ponena za kapangidwe ndi ntchito ya nembanemba selo, nkofunika kuona kuti mu ulaliki masiku ano nembanemba monga chitsanzo madzimadzi Mose, anali kuyezedwa ndi asayansi mu 1972 ndi woimba ndi Nicholson. lingaliro lawo akuganizira mbali zitatu zazikulu za kapangidwe ka Kakhungu lapansi. Yofunika Kakhungu mapuloteni zimathandiza kuti chitsanzo zithunzi kwa Kakhungu, ndipo amatha kuyenda lateral mu ndege chifukwa cha kusintha kwa zamadzimadzi bungwe. mapulotini Transmembrane komanso zomwe mafoni. Mbali yofunika ya dongosolo nembanemba ndi asymmetry ake. ndi kapangidwe ka khungu chiyani? Selo nembanemba, phata, mapuloteni ndi zina zotero. Cell ndi lofunika unit wa moyo, ndi zamoyo zonse zigwirizana maselo limodzi kapena angapo, omwe ali chotchinga chachilengedwe umene umawalekanitsa iwo kwa chilengedwe. Izi malire akunja selo umatchedwanso plasma Kakhungu. Amakhala mitundu anayi a mamolekyulu: phospholipids, mafuta m'thupi, mapuloteni ndi chakudya. Madzimadzi zithunzi chitsanzo limafotokoza Kapangidwe ka khungu nembanemba motere: kugawa zotanuka, kugwirizana akufanana mafuta ndi masamba, kotero kuti maselo onse akuyenda monga tiwolokere mu sing'anga madzi, ndipo iwo ali amasamukira laterally mkati chipolopolo izi. Mose akuimira chinachake chimene limapangidwa mbali zosiyanasiyana. Mu Kakhungu plasma izo zikufotokozedwa phospholipids, mamolekyulu mafuta m'thupi, mapuloteni ndi chakudya.

phospholipids

Phospholipids m'gulu kapangidwe zoyambirira za khungu nembanemba. mamolekyulu awa awiri osiyana kumapeto: mutu ndi mchira. Mapeto mutu zizindikiro mankwala gulu ndi hydrophilic. Izi zikutanthauza kuti umalakalaka mamolekyulu madzi. Mchira tichipeza hydrogen ndi mpweya maatomu, wotchedwa unyolo mafuta acid. unyolo Awa ndi hydrophobic, iwo samakonda kusakaniza ndi tinthu madzi. Zimenezi zikufanana ndi zomwe zimachitika pamene inu mafuta m'madzi, kutanthauza zilibe kupasuka mu izo. Features wa khungu nembanemba dongosolo zokhudzana otchedwa zamadzimadzi bilayer, chomwe phospholipids. Hydrophilic mankwala mitu nthawi pabwino kumene kuli madzi mu mawonekedwe a madzimadzi okhudza maselo ambiri ndi extracellular. The michira hydrophobic wa phospholipids mu nembanemba ndi bungwe mu njira yakuti kuwasunga kuchokera mmadzi.

Mafuta, mapuloteni ndi chakudya

Kumva mawu "mafuta", anthu amaganiza kuti ndi oipa. Koma kwenikweni, mafuta ndi yofunika zikuluzikulu za nembanemba selo. molekyulu ake tichipeza mphete zinayi hydrogen ndi mpweya maatomu. Iwo hydrophobic ndi amapezeka pakati pa micira hydrophobic mu zamadzimadzi zina kuti adzipeza wosanjikiza. kufunika ndicho kukhala kugwirizana, iwo kulimbikitsa Kakhungu ndi, kuteteza mphambano. mafuta mamolekyulu komanso kugwira michira phospholipid kubwera mu kukhudzana ndi solidifies. Izi zipangitsa fluidity mosavuta. Kakhungu mapuloteni ndi ntchito ya michere kuti imathandizira zochita mankhwala, kuchita monga zolandilira kwa mamolekyulu kapena zinthu poyendetsedwa selo nembanemba.

Chakudya, kapena dzuwa zimapezeka kokha pa mbali extracellular wa khungu nembanemba. Pamodzi iwo apanga glycocalyx. Imakhala cushioning ndi kuteteza nembanemba plasma. Yachokera pa nyumba ndi mitundu ya chakudya m'thupi glycocalyx maselo akhoza kuzindikira ndi kudziwa ngati akufuna kukhala kumeneko kapena ayi.

mapulotini Kakhungu

Kapangidwe ka khungu nembanemba wa selo nyama ndi zodabwitsa Popanda mbali yaikulu ya mapuloteni ndi. Ngakhale izi, ali kwambiri wolephera kukula kwa ena ofunika chigawo chimodzi - lipids. Pali mitundu zitatu mapulotini Kakhungu.

• Yofunika. Iwo kwathunthu kuphimba zina kuti adzipeza wosanjikiza, ndi cytoplasm ndi sing'anga extracellular. Iwo achite zoyendera ndi kusonyeza ntchito.
• Zotumphukira. Mapuloteni Ufumuyo Kakhungu pogwiritsa electrostatic, kapena kumangidwa wa hydrogen mu pamalo awo cytoplasmic kapena extracellular. Nawo mbali kwenikweni monga yolusa zikutanthauza mapulotini yofunika.
• Transmembrane. Iwo ntchito enzymatic ndi ntchito kusonyeza, ndipo modulate kapangidwe zoyambirira za zamadzimadzi zina kuti adzipeza wosanjikiza Kakhungu.

Nchito ya nembanemba kwachilengedwenso

Zotsatira hydrophobic amene amalamulira khalidwe la hydrocarbon mu madzi, kulamulira nyumba popangidwa ndi lipids Kakhungu ndi mapuloteni Kakhungu. Ambiri nembanemba katundu atakamba onyamula zamadzimadzi zina kuti adzipeza zigawo, kupanga dongosolo m'munsi kwa nembanemba amalandira. Yofunika mapuloteni Kakhungu ndi pang'ono zobisika zamadzimadzi zina kuti adzipeza wosanjikiza. mapulotini Transmembrane ndi gulu lapadera la amino zidulo mu ndondomeko yawo yaikulu.

Zotumphukira Kakhungu mapulotini ofanana kwambiri sungunuka, koma iwonso umanena nembanemba lapansi. nembanemba apadera selo apadera ntchito foni. Pamene dongosolo ndi ntchito za nembanemba selo zimakhudza thupi? Mmene kumanga nembanemba kwachilengedwenso zimadalira kuonetsetsa magwiridwe a chamoyo wonse. Kuyambira organelles okhudza maselo ambiri, extracellular ndi selo foni ankachita, nyumba Kakhungu ndi koyenera kuti bungwe ndi ntchito za ntchito kwachilengedwenso. Yambiri ya structural ndi zinchito sizachilendo kuti mabakiteriya, maselo eukaryotic ndi kuphimba mavairasi. nembanemba amalandira inamangidwa pa zamadzimadzi zina kuti adzipeza wosanjikiza, zomwe zimabweretsa pamaso pa nambala ya makhalidwe ofanana. mapulotini Kakhungu zosiyanasiyana ntchito yeniyeni.

• Amazilamulira. The plasma nembanemba maselo chimatanthauza malire a mogwirizana selo chilengedwe.
• Mayendedwe. Okhudza maselo ambiri selo nembanemba ogaŵikana midadada ingapo zinchito ndi zosiyanasiyana mkati, omwe imayendetsedwa ndi zofunika zoyendera ntchito molumikizana ndi permeability ulamuliro.
• Signal transduction. Kakhungu maphatikizidwe imapereka limagwirira kwa okhudza maselo ambiri vesicular chenjezo ndi kuteteza mitundu yonse ya mavairasi momasuka kulowa selo.

Ubwino ndi mfundo

Kapangidwe ka Kakhungu lakunja kwa selo amakhudza thupi lonse. Iwo amagwira ntchito yofunika kwambiri pofuna kuteteza kukhulupirika, kulola malowedwe a zipangizo yekha anasankha. Ndi maziko abwino kwa kukonza cytoskeleton ndi khoma khungu, amene amathandiza kukhalabe mawonekedwe selo. Lipids zimapanga pafupifupi 50% ya unyinji wa nembanemba ya maselo ambiri, ngakhale zimasiyanasiyana malinga ndi mtundu wa Kakhungu. Kapangidwe ka akunja selo nembanemba nyama ndi zovuta zambiri, pali zili zinayi phospholipid. An chuma chofunika wa zamadzimadzi zina kuti adzipeza zigawo ndi kuti iwo azikhala ngati madzi ziwiri ooneka enieni amene mamolekyulu munthu ndi ufulu atembenuza ndi kusuntha mbali lateral. fluidity Izi - ichi ndi chuma chofunika nembanemba, amene anatsimikiza malinga kutentha ndi zamadzimadzi zikuchokera. Chifukwa hydrocarbon mphete dongosolo mafuta n'chofunikira kudziwa nembanemba fluidity. Kusankha permeability wa nembanemba lofuna mamolekyulu ang'ono amalola selo kuwayang'anira ndi kukhalabe akuphatikizapo mkati.

Poganizira kapangidwe ka maselo (maselo, phata, ndi zina zotero), tinganene kuti chamoyo - izo amadzipweteka m'malangizo dongosolo kuti popanda thandizo akhoza Usadzipweteka wekha ndi nthawizonse kufunafuna njira kuti abwezeretse ndi kuteteza uziyenda bwino lililonse selo.