Te Tikanga Kawe Kaha i roto i ngā Pūtau
He tikanga nui te kawe hohe e āhei ai ngā pūtau ki te pupuri i te ora. Kāore i rite ki te kawe kore mahi, e puta ana i te pikinga kukū (mai i te kukū teitei ki te iti) me te kore e hiahiatia he pūngao, ka nekehia e te kawe hohe ngā matū ki te pikinga kukū, ki te pikinga hiko rānei. Ko te tikanga o tēnei ka "akihia" e ngā pūtau ngā ngota ngota kia neke mai i te wāhi iti te kukū ki te wāhi nui te kukū. Me whakamahi pūngao tēnei tukanga, ko te nuinga i roto i te ahua o te ATP (adenosine triphosphate), ā, kei roto ko ngā pūmua kiriuhi motuhake. He mea nui te kawe hohe mō te pupuri i te taurite katote, te kawe i ngā matūkai, te tango i ngā para, me te tautoko i ngā mahi ā-tinana pēnei i ngā nekehanga io me te whakaheke uaua.
He aha i hiahia ai ngā pūtau ki te kawe hohe?
He mea whiriwhiri te uru o te kiriuhi toto. He maha ngā ngota, inā koa ngā katote kua utua (Na⁺, K⁺, Ca²⁺, Cl⁻) me ngā ngota porotaka nui (kurukose, waikawa amino ), kāore e taea te uru ngāwari ki te paparanga phospholipid. Heoi, me whakahaere e ngā pūtau te kukū o ēnei ngota kia mau tonu ai te mahi matū koiora pumau. Hei tauira, me rerekē te kukū o ngā katote konutai me te pāhare pāporo i roto i ngā pūtau io hei whakaputa i te pūmanawa kiriuhi. Ki te kore he kawe hohe, ka ngaro te pikinga katote nā te horapa, ā, ka ngoikore te mahi a te pūtau .
Hei tāpiri atu, he maha ngā wā kei roto i te taiao o waho ngā matū e rerekē ana i ngā hiahia o te pūtau. Hei tauira, me mimiti e ngā pakiaka tipu ngā katote kohuke mai i te oneone ahakoa he iti rawa te kukū o ēnei kohuke. Mā te kawe kaha, ka taea tonu e ngā pūtau tipu te "tango" i ngā katote nui ki te rerekētanga kukū.
Te mātāpono taketake: e ārai ana i te pikinga me te hiahia ki te pūngao
I te taumata ngota ngota, ko te kawe hohe ka whakahaerehia e ngā pūmua kiriuhi e kiia nei ko ngā papu, ko ngā kaikawe rānei. He wāhi here motuhake tō ēnei pūmua mō ngā ngota ngota motuhake. Kia herea te ngota ngota, ka huri te āhua o te pūmua, ka nekehia te ngota ki tērā taha o te kiriuhi. Me whai pūngao tēnei huringa āhua. I roto i te kawe hohe tuatahi, ka whiwhi tika te pūngao mai i te waikura ATP. I roto i te kawe hohe tuarua, ka puta te pūngao mai i te rōnaki katote i whakatūria i mua e te kawe hohe tuatahi.
Te kawe matua hohe
Ko te kawe hohe tuatahi he tikanga kawe e whakamahi tika ana i te pūngao mai i te pakaru o te ATP. Nō roto mai ngā papu kiriuhi i roto i tēnei pūnaha i ētahi whānau pūmua nui, pērā i te ATPase momo-P, te ATPase momo-V, me ngā kawe ABC.
1. Papu Konutai-Pōtasium (Na⁺/K⁺-ATPase)
Ko tētahi o ngā tauira rongonui ko te papu konutai-pāhare pākawa, e kitea ana i roto i ngā kiriuhi pūtau kararehe . Ka pupuri tēnei papu i te kukū iti o te Na⁺ i roto i te pūtau, me te kukū teitei o te K⁺ i roto. I roto i te huringa kotahi, ka nekehia e te papu e 3 ngā iona Na⁺ i waho o te pūtau me ngā iona K⁺ e 2 ki roto i te pūtau mā te whakamahi i te 1 ngota ATP. Nā te mea he nui ake te utu pai e wehe atu ana i te pūtau, he hikohiko tēnei papu, ā, ka āwhina ki te waihanga i te pūmanawa kiriuhi kino i roto i te pūtau.
He whānui te mahi a te Na⁺/K⁺-ATPase: te pupuri i te rahinga o te pūtau (te ārai i te pupuhi o ngā pūtau), te tautoko i te tuku i ngā nekehanga io, me te whakarato i te pikinga Na⁺ e tika ana mō te kawe tuarua (hei tauira, te kawe tahi i te huka).
2. Papu Konupūmā (Ca²⁺-ATPase)
He katote nui te konupūmā mō te tohu ā-roto. Heoi, me pupuri kia iti rawa te kukū o te Ca²⁺ i roto i te cytoplasm kia taea ai te whakahaere tere me te tika i ngā tohu konupūmā. Ka nekehia e te papu Ca²⁺ te konupūmā i waho o te cytoplasm, i waho o te pūtau (kirikiri plasma) ki roto rānei i ngā whekau pēnei i te reticulum endoplasmic , i te sarcoplasm rānei (i roto i ngā pūtau uaua). He mea nui tēnei tikanga mō te whakangā o te uaua i muri i te whakahekenga me te whakahaere i ngā ara tohu pūtau.
3. Papu Pūtorino (H⁺-ATPase)
I roto i ngā pūtau tipu, harore, me te kitakita, he mahi nui tā ngā papu pūrotu ki te whakatū i ngā pikinga hikohiko. Ka nekehia e ēnei papu ngā iona H⁺ puta noa i te kiriuhi, ka hangaia he rerekētanga pH me te rerekētanga pūmanawa hiko. Kātahi ka taea te whakamahi i tēnei pikinga pūrotu hei akiaki i te kawe hohe tuarua, pērā i te tango matūkai. I roto i ngā whekau eukaryotic pērā i ngā lysosomes, ka mahi anō ngā papu pūrotu momo-V ki te whakakawa i te lumen o ngā whekau kia taea ai e ngā whākōkī waiora te mahi pai.
4. Kaikawe ABC
Ko ngā kaikawe ABC (ATP-Binding Cassette) he rōpū pūmua e whakamahi ana i te ATP hei neke i ngā momo ngota ngota, tae atu ki ngā lipid, te cholesterol, me ngā rongoā. Ka whai wāhi ētahi kaikawe ABC ki te ātete rongoā i roto i ngā pūtau matepukupuku mā te pupuhi i ngā rongoā ki waho o te pūtau, ka whakaiti i te whai huatanga o te rongoā. E whakaatu ana tēnei ehara i te mea he ariā taketake noa iho te kaikawe hohe i roto i te koiora engari he mea nui anō hoki i roto i te rongoā.
Te kawe hohe tuarua
He rerekē tēnei i te kawe hohe tuatahi, e whakamahi tika ana i te ATP, ka whakamahia e te kawe hohe tuarua te pūngao kua rongoatia ki roto i ngā rōnaki katote (ko te tikanga ko te Na⁺, ko te H⁺ rānei). I whakatūria i mua ēnei rōnaki e ngā papu tuatahi. E rua ngā tikanga kawe tuarua: ko te symport (cotransport) me te antiport.
1. Kawemai (kawe-tahi)
I roto i te hononga tahi, e rua ngā matū e nekehia ngātahitia ana i te ahunga kotahi. Ko tētahi tauira matarohia ko te kawe tahi o te Na⁺-glucose i roto i ngā pūtau epithelial whekau me ngā ngongo whatukuhu. Ka neke te Na⁺ ki roto i te pūtau i tōna pikinga (mai i te tihi ki waho ki te iti ki roto), ā, ka whakamahia te pūngao mai i te nekehanga o te Na⁺ hei kukume i te hukahuka ki roto i tōna pikinga kukū. Mā tēnei tikanga ka taea e te tinana te mimiti pai i te hukahuka ahakoa kua tino teitei te kukū hukahuka i roto i te pūtau.
Haunga te kurukose, he maha ngā waikawa amino ka mimitihia mā te tikanga honohono me te Na⁺.
2. Ārai-taunga
I roto i te pūmua ārai-ira, e rua ngā matū e kawehia ana i ngā taha rerekē. Hei tauira, ko te whakawhiti Na⁺/Ca²⁺ i roto i ētahi momo pūtau, e whakamahi ana i te rerenga mai o te Na⁺ hei pana i te Ca²⁺ ki waho o te pūtau. Ka āwhina tēnei tikanga ki te pupuri i ngā taumata Ca²⁺ iti o te cytoplasm, inā koa i roto i ngā kiko hikohiko pērā i te ngākau me ngā neuron.
Te kawe i ngā uaua: te endocytosis me te exocytosis
Haunga te kawe i ngā pūtau mā roto i ngā pūmua kawe, ka kawe hoki ngā pūtau i ngā pūtau mā te hanganga o ngā vesicle. E hiahiatia ana he pūngao mō tēnei tukanga, ā, ka uru atu hoki ngā huringa ki te āhua o te membrane me te cytoskeleton.
Endositosis
Ko te endocytosis te tukanga o te tango rauemi ki roto i te pūtau mā te kiriuhi e piko ana ki roto hei hanga i tētahi vesicle. He maha ngā momo endocytosis:
1. Te Whakapūngao: te "kai" i ngā matūriki nunui pērā i te huakita, e mahia ana e ngā pūtau ārai mate (hei tauira, ngā macrophage).
2. Pinocytosis: te kai kore-motuhake o ngā wai me ngā ngota iti.
3. Te endocytosis e whakahaerehia ana e te kaiwhakawhiwhi: he tukanga whiriwhiri e whakamahi ana i ngā kaiwhakawhiwhi membrane hei hopu i ngā ngota motuhake (hei tauira, te LDL/cholesterol).
Te whakaputanga o te haukoti
Ko te exocytosis te ritenga kē o te endocytosis, arā, ko te tukunga o ngā matū ki waho o te pūtau mā te hanumitanga o ngā vesicles ki te membrane plasma. He mea nui te exocytosis i roto i te whakaputanga o ngā homoni (hei tauira, te insulin), te tukunga o ngā neurotransmitters i ngā synapses, me te tukunga o ngā pūmua me ngā whākōkī.
Ngā āhuatanga e awe ana i te kawe hohe
He maha ngā āhuatanga e pāngia ai te tere o te kawe kaha, tae atu ki:
– Te wātea o te ATP: ki te heke te hanga ATP (hei tauira i roto i ngā āhuatanga koretake o te hāora), ka heke te mahi a te papu.
– Te maha me te ngohe o ngā pūmua kawe: ka taea e te whakahaere ira me te whakarerekētanga pūmua te whakanui, te whakaiti rānei i te maha o ngā papu.
– Te pāmahana me te pH: ka pā ki te hanganga pūmua me ngā tere tauhohenga whākōkī.
– Te noho mai o ngā aukati: ka taea e ētahi paitini, e ētahi rongoā rānei te aukati i ētahi papu, ā, he pānga nui tēnei ki te mahi a te pūtau.
Whakamutunga
He tukanga nui te kawe kaha e āhei ai ngā pūtau ki te whakahaere tika i ō rātou hanganga ā-roto. Mā te whakamahi i te pūngao—mai i te ATP (te kawe kaha tuatahi) mai i ngā pikinga katote rānei (te kawe kaha tuarua)—ka taea e ngā pūtau te neke i ngā katote me ngā ngota nui ki ngā pikinga kukū. Hei tāpiri, mā te kawe vesicular, pērā i te endocytosis me te exocytosis, ka taea te neke i ngā rahinga nui o ngā rauemi. Ka mahi tahi ēnei tikanga katoa ki te pupuri i te homeostasis, te tautoko i te whakawhitiwhiti kōrero i waenga i ngā pūtau, me te whakarite kia taea e ngā pūtau te urutau ki ngā huringa taiao. Ki te kore he kawe kaha, ka ngaro te mana whakahaere o ngā pūtau i tō rātou taurite matū, ā, ka mutu te mahi tika o ngā mahi ora maha.
