Hanganga me te Mahi o ngā Kiriuhi Pūtau
Ko te kiriuhi pūtau tētahi o ngā wāhanga tino nui o te oranga o te pūtau. Tata ki ngā tukanga matua katoa e āhei ai ngā pūtau ki te ora—mai i te whakahaere i te urunga me te putanga o ngā matū, ki te whakawhitiwhiti kōrero i waenga i ngā pūtau, ki te whakaputa pūngao—e uru ana te kiriuhi pūtau. Ehara i te mea ko tēnei kiriuhi anake te "ārai" i waenganui i te roto o te pūtau me tōna taiao, engari he kaiwhakahaere matua hoki mō ngā mahi koiora. Hei mārama ki te mahi a ngā pūtau, me mārama tātou ki te hanganga me te mahi a te kiriuhi pūtau i tōna katoa.
Te Mārama ki ngā Kiriuhi Pūtau
Ko te kiriuhi pūtau (kiriuhi plasma) he paparanga angiangi e karapoti ana i te pūtau, e wehe ana i ngā mea o roto o te pūtau (cytoplasm) mai i te taiao o waho. He kiriuhi whiriwhiri tēnei, arā, ko ētahi matū anake ka taea te haere mā roto, ko ētahi kua āraia. He mea nui tēnei āhuatanga whiriwhiri hei pupuri i ngā āhuatanga o roto o te pūtau ahakoa ngā huringa o te taiao o waho.
Kei roto i ngā pūtau katoa ngā kiriuhi pūtau, arā, ngā pūtau prokaryotic (pērā i te huakita) me ngā pūtau eukaryotic (pērā i ngā pūtau kararehe me ngā pūtau tipu). I roto i ngā pūtau tipu , haunga te kiriuhi pūtau, he pakitara pūtau pakari ake anō hoki, engari ko te kiriuhi pūtau tonu te hanganga matua e whakahaere ana i te kawe i ngā matū.
Hanganga Kiriuhi Pūtau: Tauira Mosaic Wai
E whakamāramahia ana te hanganga o ngā kiriuhi pūtau hou e te tauira mosaic wai. E kī ana tēnei tauira he mea tito ngā kiriuhi mai i ngā momo ngota rerekē kua whakaritea kia rite ki te mosaic, ā, ka taea e ō rātou wāhanga te neke ngāwari (maeneene). Mā tēnei ngāwari ka taea e te kiriuhi te urutau, te hanga i ngā pūwero, me te taunekeneke ki tōna taiao.
Ko te tikanga, ko ngā kiriuhi pūtau he mea hanga mai i:
1. Paparua Phospholipid (Paparua)
Ko te wāhanga matua o ngā kiriuhi pūtau ko ngā phospholipid, arā, he ngota ngako e rua ngā wāhanga motuhake:
– Ko ngā upoko wai-aroha ki te wai (e anga ana ki waho, ki roto hoki i te pūtau) i a rātou e taunekeneke ana me ngā wai.
– He hiku wai-kore (e kino ana ki te wai), e anga atu ana tetahi ki tetahi i waenganui o te kiriuhi hei karo i te wai.
Ka hangaia e tēnei whakaritenga he paparanga rua phospholipid e mahi ana hei ārai tuatahi ki ētahi matū, inā koa ngā ngota porowhita, ngā ngota rānei kua utaina. Ka whakaratohia hoki e tēnei paparanga te ngāwari o te kiriuhi me te kaha ki te "whakatika" i a ia anō i muri i ngā kino iti.
2. Ngā Pūmua Kiriuhi
He wāhanga nui ngā pūmua e mau ana ki roto, e piri ana rānei ki ngā kiriuhi. I runga i tō rātou wāhi noho, ka wehea ngā pūmua kiriuhi ki:
– Ngā pūmua whakauru (transmembrane): ka uru ki roto i te paparanga phospholipid, ka mahi pinepine hei awa, hei kaikawe rānei.
– Ngā pūmua taha: e piri ana ki te mata o te kiriuhi, ā, he maha ngā wā ka whai wāhi ki te whakapakari i ngā hanganga, ngā whākōkī, te whakawhitiwhiti kōrero rānei ki ngā pūtau.
Ka taea e ngā pūmua kiriuhi te mahi hei kaiwhakawhiwhi tohu, hei whākōkī, hei hongere katote, hei mōhio ki ngā pūtau, tae atu ki ngā huānga here ki te anga o te pūtau (cytoskeleton). Nā te noho mai o ngā pūmua, ehara te kiriuhi i te paparanga ngako kore mahi noa iho, engari he pūnaha tino hihiri, kaha hoki.
3. Korekoretere
I roto i ngā pūtau kararehe, kei roto i ngā phospholipids te cholesterol. Ko ngā mahi a te cholesterol ko:
– Kia mau tonu te pumau o te kiriuhi kia kore ai e tino mārō rawa, e tino wai rawa rānei.
– Ka whakahaere i te rere o te kiriuhi i ngā pāmahana rerekē.
– Ka āwhina i te kiriuhi kia ātete ake ki ngā huringa taiao.
I ngā pāmahana iti, ka ārai te cholesterol i te piri rawa o ngā phospholipids, ka ārai i te tio o te kiriuhi. I ngā pāmahana teitei, ka ārai te cholesterol i te nekehanga o ngā phospholipids, ka ārai i te wai rawa o te kiriuhi.
4. Ngā Warowaihā (Ngā Pūmua me ngā Ngakorikiripa)
Kei te mata o waho o te kiriuhi, kei reira ngā mekameka warowaihā e piri ana ki ngā pūmua, ki ngā ngako rānei:
– Glycoprotein: warowaihā + pūmua
– Ngā Glycolipids: ngā warowaihā + ngā lipids
He mea nui ēnei warowaihā mō te mōhio ki ngā pūtau, te hanganga kiko, te whakawhitiwhiti kōrero i waenga i ngā pūtau, me ngā urupare ārai mate. Hei tauira, he "tohu" motuhake kei ngā pūtau o te tinana e āhei ai te pūnaha ārai mate ki te wehewehe i waenga i ōna ake pūtau me ngā pūtau ke.
Te Mahi a te Kiriuhi Pūtau
He maha ngā mahi e hono tahi ana te kiriuhi pūtau. Ko ngā mahi matua o te kiriuhi pūtau ēnei:
1. Ngā Rohe Pūtau me ngā Kaitiaki
Ko te mahi matua o te kiriuhi pūtau ko te ārai i ngā ihirangi o te pūtau kia kore e hanumi tika ki te taiao o waho. Ka tiakina e te kiriuhi ngā whekau me ngā wāhanga o te pūtau mai i ngā huringa ohorere o waho o te pūtau. Mā te kiriuhi ka taea e te pūtau te pupuri i ngā āhuatanga o roto e āhua pumau ana (homeostasis).
2. Whakahaere i te Kawenga Matū (Ka Taea te Whakauru)
Ka whakahaerehia e ngā kiriuhi te urunga me te putanga o ngā matū mā roto i ngā momo tikanga kawe, tae atu ki:
a. Te kawe ā-ngāwari (kāore he pūngao):
– Te horapa māmā: ka uru tika atu ngā ngota iti kore-poari pērā i te O₂ me te CO₂ mā roto i te paparanga lipid.
– Te horapa ngāwari: ka tomo mai ngā ngota ngota, ngā katote rānei mā te awhina o ngā pūmua hongere, ngā pūmua kawe rānei, hei tauira, te kurukose mā roto i ngā pūmua kawe.
– Te osmosis: te nekehanga o te wai mai i te kukū wairewa iti ki te kukū wairewa teitei mā roto i te kiriuhi, he maha ngā wā mā roto i ngā pūmua aquaporin.
b. Te kawe hohe (e hiahiatia ana te pūngao/ATP):
– Ka nekehia ngā matū ki te ritenga rerekē o te pikinga kukū, hei tauira, te papu konutai-pāhare pākawa (Na⁺/K⁺) he mea nui tēnei mō ngā nekehanga io me te taurite o ngā katote.
c. Te kawe i ngā uaua:
– Endositosis: te whakauru i ngā matū nunui ki roto i ngā pūtau (hei tauira, te phagocytosis i roto i ngā pūtau toto mā).
– Te exocytosis: te tukunga o ngā matū mai i ngā pūtau, hei tauira te whakaputanga o te homoni, te whākōkī rānei.
Mā tēnei tikanga, ka taea e ngā pūtau te whiwhi matūkai, te tango i ngā para, me te pupuri i te taurite o te katote me te wai.
3. Kaiwhiwhi Tohu me te Kaituku (Whakawhitiwhitinga Pūtau)
Kei roto i ngā kiriuhi pūtau ngā kaiwhakawhiwhi (ko te tikanga he pūmua) ka taea te kite i ngā tohu matū pēnei i ngā homoni, ngā neurotransmitters, ngā āhuatanga tipu rānei. Ina herea he tohu ki tētahi kaiwhakawhiwhi, ka puta he raupapa o ngā tauhohenga i roto i te pūtau e kiia nei ko te whakawhiti tohu. Mā tēnei tukanga ka taea e ngā pūtau te urupare ki ngā huringa taiao, pēnei i te whakanui ake i te pākia o te tinana, te wehewehe, te whakaputa rānei i ngā pūmua motuhake.
4. Te Mōhiotanga Pūtau me te Urupare Ārai Mate
Ko ngā mekameka warowaihā i roto i ngā glycoprotein me ngā glycolipids hei "tuakiri" pūtau. He mea nui tēnei mō:
– te mōhiotanga i waenga i ngā pūtau i te wā e hangaia ana te kiko,
– te tukanga whakapiri pūtau,
– te urupare ārai mate ina kitea e te tinana tētahi huaketo.
Ko tēnei taupatupatu o ngā tohu te take hoki e hiahiatia ai te taurite o te kiko i roto i ngā whakawhitinga okana hei ārai i te panga.
5. Wāhi Mahi Ngā whākōkī me ngā tauhohenga matū koiora
Ka piri ētahi whākōkī ki ngā kiriuhi pūtau, ā, ka whakahaere i ngā tauhohenga matū koiora motuhake. Mā te whakanoho i ngā whākōkī ki runga i ngā kiriuhi, ka taea e ngā pūtau te whakahaere i ngā tauhohenga me te whai hua ake nā te mea he tata ake ngā matū tauhohenga ki a rātou anō. I roto i ētahi rauropi, ka whai wāhi tika ngā kiriuhi ki te whakaputa pūngao.
6. Te Hanga Hanganga me te Pupuri i te Āhua o te Pūtau
Ka taunekeneke te kiriuhi pūtau ki te angaanga o roto, me te angaanga o waho o te pūtau. Ka āwhina ēnei taunekeneke i te pūtau:
– te pupuri i te āhua,
- neke,
– te ātete ki te ahotea ā-mīhini,
– te hanga i tētahi whatunga auau.
I roto i ngā pūtau kararehe, he mea nui te hononga o te kiriuhi ki te angaanga pūtau mō ngā tukanga pēnei i te wehenga pūtau me te nekehanga pūtau.
Ngā Rerekētanga o ngā Kiriuhi Pūtau i roto i ngā Momo Pūtau Rerekē
Ahakoa he rite tonu ngā mātāpono hanganga, he rerekē ngā kiriuhi pūtau i runga i te momo pūtau:
– Ngā pūtau kararehe: he nui te cholesterol, ā, he maha ngā kaiwhakawhiwhi me ngā pūmua kawe.
– Ngā pūtau tipu: kei raro i te pakitara pūtau te kiriuhi pūtau; he pūmua kawe motuhake kei roto hei whakawhiti matū i waenga i ngā pūtau mā roto i ngā plasmodesmata.
– Ngā pūtau prokaryotic: he wāhi nui ō rātou kiriuhi mō ētahi tukanga pākia nā te mea kāore i a rātou he whekau e herea ana ki te kiriuhi pērā i te mitochondria.
Whakamutunga
He hanganga nui te kiriuhi pūtau e tautuhi ana i ngā rohe o te ora i te taumata pūtau. He mea tito mai i tētahi paparanga rua phospholipid me ngā pūmua, te cholesterol, me ngā warowaihā, he hihiri, he whiriwhiri hoki te kiriuhi pūtau. Ehara i te mea he tiaki anake tana mahi engari he whakahaere anō hoki i te kawe matū, he pokapū whakawhitiwhiti kōrero, he pūnaha mōhio pūtau, he wāhi mō te mahi whākōkī, me te tautoko hanganga. Mā te mārama ki te hanganga me te mahi a te kiriuhi pūtau, ka taea e tātou te mārama ki te pupuri a ngā pūtau i te homeostasis, te urutau ki tō rātou taiao, me te whakahaere i ngā mahi koiora uaua.
Ki te hiahia koe, ka taea e au te tāpiri i tētahi whakaahua māmā o te tauira mosaic wai, te whakarāpopoto rānei i ngā kōrero matua kia māmā ake ai te ako.
