Ukusebenza Okusebenzayo Nokungenzi lutho

-Delile

• Izibonelo zezokuthutha
• Izibonelo zokuthutha okusebenzayo

Ubizwa ngegama ukuthuthwa kwamaseli ekushintshaneni kwezinto phakathi kwengaphakathi leseli nemvelo yangaphandle lapho kutholakala khona. Lokhu kwenzeka nge ulwelwesi lwe-plasma, okuyisithiyo esingahlukeki esinqamula iseli.

Ukuthuthwa kwamaselula kubalulekile ekufakeni izakhi zomzimba nezinto ezichithwe emvelweni, nokuxoshwa kwemfucuza noma izinto ezenziwe ngomzimba ngaphakathi kweseli, njengoku amahomoni noma ama-enzyme. Ngokwesiqondiso sayo sokuhamba kwendaba nezindleko zayo zamandla, sizokhuluma ngalokhu:

• Ezokuthutha ezingenzi lutho. Ngokuthanda i-gradient yokuhlushwa, okungukuthi, ukusuka kokuphakathi okugxile kakhulu kuya kokungagxilile kakhulu, kwenzeka ngokusakazeka ngolwelwesi futhi akunazindleko zamandla, ngoba isebenzisa ngokunenzuzo ukunyakaza okungahleliwe kwama-molecule (i-kinetic yawo amandla). Kunezinhlobo ezine zezithuthi ezingenzi lutho:
  • Ukusabalalisa okulula. Izinto zisuka endaweni egxilwe kakhulu ziye ekugxilisweni okuncane kuze kufike amazinga alinganayo.
  • Ukusatshalaliswa okwenziwe lula. Ezokuthutha zenziwa ngamaphrotheni akhethekile ezokuthutha atholakala ngaphakathi kolwelwesi lweseli.
  • Ukuhlunga. Ulwelwesi lwe-plasma lunama-pores lapho izinto ezinosayizi othile zingangena ngaphakathi kungcindezi lwe-hydrostatic.
  • I-Osmosis. Ngokufana nokusabalalisa okulula, kuya ngesinyathelo se- ama-molecule amanzi ngokusebenzisa ulwelwesi, ngenxa yengcindezi yaphakathi nokukhetha kwayo.

• Ukuthutha okusebenzayo. Ngokungafani nokungenzi lutho, kusebenza ngokungahambisani ne-gradient yokuhlushwa (kusuka endaweni engagxilile kakhulu kuya kokugxilwe kakhulu), ngakho-ke inezindleko zamandla weselula. Lokhu kuvumela amaseli ukuthi aqoqe izinto azidingayo ngenqubo yawo yokuhlanganisa.

Izibonelo zezokuthutha

1. Ukuchithwa kusendlalelo se-phospholipid. Ngakho-ke, izinto eziningi zingena engqamuzaneni, njengamanzi, umoya-mpilo, isikhutha, amavithamini ancibilikayo anamafutha, ama-steroids, i-glycerines, nama-alcohol anesisindo esiphansi.
2. Ukungena ngemigudu ephelele yamaprotheni. Ezinye izinto ze-ionic (ezifakwe ngogesi), njenge-sodium, i-potassium, i-calcium noma i-bicarbonate, zidlula kulwelwesi oluholwa yiziteshi kanye amaprotheni okukhethekile kulokhu, kuncane kakhulu.
3. I-glomeruli yezinso. Bahlunga igazi ezinsweni, balikhumula i-urea, i-creatinine nosawoti, ngenqubo ye-ultrafiltration eyenziwa ngama-capillaries, evimbela ukudlula kwezinto ezinkulu futhi ikhiphe ezincane ngenxa yengcindezi yento uqobo.
4. Ukumuncwa kwe-glucose. Amaseli agcinwa njalo enesisindo esiphansi se-glucose, okwenza ukuthi ihlale igeleza ngokusakazeka ngaphakathi kwawo. Ukwenza lokhu, amaprotheni e-transporter ayifaka ngaphakathi bese eyiguqula ibe yi-glucose-6-phosphate.
5. Isenzo se-insulin. Le hormone efihliwe amanyikwe ithuthukisa ukusakazeka koshukela egazini kumaseli, kunciphisa ubukhona boshukela egazini, kufeza indima umngameli.
6. Ukusabalalisa kwegesi. Ukusabalala okulula kuvumela ukungena kwamagesi akhiqizwa ukuphefumula, kusukela ngaphandle kuye ngaphakathi kwamaseli kusuka ekugxileni kwawo egazini. Ngale ndlela i-CO iyaxoshwa₂ futhi i-oxygen iyasetshenziswa.
7. Ukujuluka. Ukukhishwa kwesithukuthuku esikhunjeni kwenziwa yi-osmosis: uketshezi luphuma luthwale ubuthi nezinye izinto ngalo.
8. Izimpande zezitshalo. Zinolwelwesi olukhethayo oluvumela amanzi namanye amaminerali ukuthi angene ngaphakathi kwesitshalo, bese eluthumela emaqabungeni ukuze enze i-photosynthesize.
9. Ukumuncwa emathunjini. Amaseli we-epithelial wamathumbu amunca amanzi nezinye izakhi esitokisini, ngaphandle kokuwavumela angene egazini. Ukukhetha okwenziwe nakho kwenzeka ngokungenzi lutho, ngokusebenzisa i-electrolyte gradient.
10. Ukukhishwa kwama-enzyme nama-hormone egazini. Kuvame ukukhiqizwa yimishini yokuhlushwa okuphezulu kwamaseli, ngaphandle kwezindleko ze-ATP.

Izibonelo zokuthutha okusebenzayo

1. Iphampu ye-sodium-potassium. Kuyindlela yolwelwesi lweseli evumela, ngokusebenzisa iprotheni ethutha, i-sodium ukuthi ixoshwe ngaphakathi kwengqamuzana bese kufakwa i-potassium, kugcinwe ama-gradients e-ion (i-sodium ephansi ne-potassium eningi) kanye ne-polarity kagesi efanelekile.
2. Iphampu ye-calcium. Elinye iprotheni lokuthutha elikhona kulwelwesi lweseli, livumela i-calcium ukuthi ithwelwe ngokumelene ne-gradient yayo ye-electrochemical, kusuka ku-cytoplasm kuya ngaphandle.
3. I-Phagocytosis. Amaseli egazi amhlophe avikela umzimba afaka, ngokusebenzisa amasaka olwelwesi lwe-plasma, izinhlayiya zangaphandle esizozixosha kamuva.
4. I-Pinocytosis. Enye inqubo ye-phagocytization idlula ngokungena ngaphakathi kolwelwesi oluvumela ukungena kuketshezi lwezemvelo. Kuyinto eyenziwa yiqanda ngesikhathi sokuvuthwa kwalo.
5. I-Exocytosis. Ngokuphikisana ne-phagocytization, ikhipha izakhi zokuqukethwe kwamaselula ngamasaka aluhlaza aphumela ngaphandle, aze ahlangane nolwelwesi futhi avulekele ngaphandle. Le yindlela ama-neurons axhumana ngayo: idlulisa okuqukethwe kwe-ionic.
6. Ukutheleleka nge-HIV. Igciwane lengculazi lingena emangqamuzaneni ngokusebenzisa ulwelwesi lwawo, libopha ama-glycoprotein akhona kungqimba lwawo lwangaphandle (ama-CD4 receptors) futhi angene ngaphakathi ngaphakathi.
7. I-Transcytosis. Inhlanganisela ye-endocytosis ne-exocytosis, ivumela ukuthuthwa kwezinto zisuke kwesinye isisetshenziswa ziye kwesinye, ngokwesibonelo, kusukela kuma-capillaries egazi kuya ezicutshini ezizungezile.
8. Ushukela phototransferase. Inqubo ejwayelekile ethile amagciwane Ini coli, equkethe ukuguqula amakhemikhali ngaphakathi kwamakhemikhali ukuheha abanye nge ukubopha okubumbene futhi ngaleyo ndlela wonge amandla amaningi.
9. Ukuthathwa kwensimbi. I-Iron ithathwa ngamagciwane amaningi ngokufihla ama-siderophores afana ne-enterobactin, ebophezela kuma-chelates akha ama-chelates abese emunca ubumbano kumagciwane, lapho kukhishwa khona insimbi.
10. Ukuthathwa kwe-LDL. Le lipoprotein ene-cholesterol esters ibanjwa yiseli ngenxa yesenzo se-apoprotein (B-100) esivumela ukungena kwaso kulwelwesi nokubola okulandelayo ama-amino acid.