He aha te Hiranga o te Huka mō te Whakaputa ATP
Ko te ATP (adenosine triphosphate) e kiia ana ko te "moni pūngao" o te tinana. Tata ki ngā mahi pūtau katoa—mai i te whakahekenga uaua me te tuku i ngā nekehanga io ki te hanganga pūmua me te kawe i ngā matū puta noa i ngā kiriuhi—me whai ATP. Heoi, kāore te ATP e rongoatia i roto i ngā rahinga nui; me whakaputa tonu e te tinana mai i ngā wahie e wātea ana. Ko tētahi o ngā wahie tino nui, e wātea ana hoki mō ngā pūtau ko te hukahuka. Ko te pātai: he aha te hiranga o te hukahuka mō te whakaputa ATP?
1. Te hukahuka: he wahie tere, he maha hoki ngā whakamahinga
He warowaihā māmā (monosaccharide) te hukahuka, koinei te pūtake matua o te pūngao mō ngā kiko maha o te tinana. I muri i tā tātou kai i ngā kai warowaihā—pērā i te raihi, te taro, te hua rākau, te kūmara rānei—ka nakunaku ngā warowaihā hei hukahuka, ā, ka mimitia ki roto i te toto. Mai i konei, ka taea te whakamahi tika i te hukahuka e ngā pūtau, ka rongoatia rānei hei glycogen i roto i te ate me ngā uaua.
Ko te painga o te hukahuka i runga i ngā atu ngota pūngao maha ko tōna maha o ngā mahi: ka taea te whakapūngao hei whakaputa ATP i raro i te nui o te hāora (ngā āhuatanga hauā) me raro hoki i te iti o te hāora (ngā āhuatanga anaerobic). Nā tēnei ngāwari ka noho te hukahuka hei kaupapa matua mō te pākia o te pūngao.
2. ATP me ngā hiahia pūngao pūtau tonu
He rite te mahi a te ATP ki tētahi pākahiko iti ka taea te whakahou. Ina pakaru te ATP ki te ADP (adenosine diphosphate) me te phosphate inorganic (Pi), ka tukuna te pūngao hei whakahaere i ngā tukanga koiora. Nā te mea e whakamahia tonutia ana te ATP, me whai ara pākia pai, pumau hoki ngā pūtau hei whakaputa.
Ka whakaratohia e te hukahuka he anga waro me ngā irahiko kaha-nui ka taea te tango i ia taahiraa mā roto i ētahi ara: te glycolysis, te huringa Krebs, me te mekameka kawe irahiko. He mea nui tēnei raupapa o ngā taahiraa nā te mea ka taea e ngā pūtau te whiwhi pūngao whai hua me te kore e "tahu" te hukahuka katoa i te wā kotahi.
3. Glycolysis: te wāhanga tuatahi o te hanga ATP kāore e whakawhirinaki ki te hāora.
Ka tīmata te mahi a te hukahuka i roto i te hanga ATP me te glycolysis, te pakaru o te ngota hukahuka kotahi (6 ngā ngota waro) kia rua ngā ngota pyruvate (3 ngā ngota waro o ia ngota). Ka puta te glycolysis i roto i te cytoplasm o te pūtau, ā, kāore e hiahiatia he hāora, he ara nui tēnei ina pāngia te tinana e te korenga o te hāora—hei tauira, i te wā e kaha ana te whakakori tinana.
I roto i te glycolysis, ka whiwhi ngā pūtau:
– ATP tika (whakapūhuitanga taumata-papa): ko te whiwhinga kupenga he 2 ATP mō ia ngota huka.
– NADH: he ngota kawe irahiko pūngao-tiketike ka taea te whakamahi i muri mai hei whakaputa i te ATP nui ake i raro i ngā āhuatanga hauropi.
Ahakoa te āhua iti o te hua ATP tika mai i te glycolysis, he mea tino nui tēnei wāhanga nā te mea:
1. ka tere te tupu,
2. ka taea te puta i roto i te nuinga o ngā pūtau,
3. ka noho hei tomokanga mō te hukahuka ki te ara pūngao e whai ake nei.
4. Ngā āhuatanga anaerobic: ka taea tonu e te huka te whakaputa pūngao
Ina kore e ranea te hāora, kāore e taea e te pyruvate i hangaia e te glycolysis te uru pai ki te wāhanga whakaputa pūngao aerobic. Engari, ka hurihia te pyruvate ki te lactate (i roto i te tangata) mā te whakapūtanga waikawa lactic. Ehara i te mea ko te whakaputa ATP tāpiri te whāinga, engari ko te whakahou i te NAD+ kia haere tonu ai te glycolysis me te whakaputa ATP, ahakoa he iti noa te tere.
Koia te take he mea nui te hukahuka mō ngā kiko e pāngia pinepine ana e te korenga o te hāora mō te wā poto, pērā i ngā uaua e kaha ana te mahi. I ēnei āhuatanga, ka whakaratohia e te hukahuka he ara "ohorere" hei pupuri i te hanga ATP.
5. Ngā āhuatanga ā-hauora: he nui te ATP ka puta mai i te hukahuka.
Mena kei te wātea te hāora, ka uru te pyruvate mai i te glycolysis ki roto i ngā mitochondria ka tukatukahia hei acetyl-CoA. Kātahi ka uru te Acetyl-CoA ki te huringa Krebs (huringa waikawa citric). I tēnei wā, ka tangohia anō te pūngao mai i te hukahuka i roto i te āhua o:
– NADH
– FADH2
– he iti noa te ATP (te GTP rānei) tika
Kātahi ka haria e te NADH me te FADH2 ngā irahiko ki te mekameka kawe irahiko i roto i te kiriuhi mitochondrial o roto. Koinei te wāhi e hangaia ai te nuinga o te ATP mā te phosphorylation oxidative. Ka āwhina ngā irahiko e rere ana i roto i te mekameka kawe irahiko ki te pupuhi i ngā proton, ka hanga he rōnaki ka whakamahia e te whākōkī ATP synthase hei "hono" i te phosphate ki te ADP, ka puta ai te ATP.
I te nuinga, ko te waikura katoa o te ngota huka kotahi i raro i ngā āhuatanga hauropi ka taea te whakaputa i te 30–32 ATP (ka rerekē pea tēnei tau i runga i te momo pūtau me te tikanga o te kawe NADH ki ngā mitochondria).
Hei whakamutunga, ehara i te mea ka taea e te huka te whakaputa ATP anake; ka taea hoki e ia te whakaputa i te nui o te ATP me te tino whai hua ina wātea te hāora.
6. He mea nui te hukahuka mō te roro me ngā toto whero.
He nui te whakawhirinaki o ētahi kiko ki te hukahuka hei pūtake pūngao:
1. Roro
He nui te pūngao e whakamahia ana e te roro hei pupuri i te mahi hiko o ngā neurons, te mahi a ngā papu katote (pērā i te Na+/K+ ATPase), me te whakahaere i ngā neurotransmitters. I raro i ngā āhuatanga noa, ka whakawhirinaki nui te roro ki te hukahuka. I te wā nohopuku roa, ka taea e te roro te whakamahi i ngā tinana ketone, engari he mea nui tonu te hukahuka.
2. Ngā pūtau toto whero (ngā erythrocytes)
Kāore he mitochondria o ngā pūtau toto whero, arā, kāore e taea e rātou te whakahaere i te huringa Krebs me te mekameka kawe irahiko. Ko te huarahi anake e whakaputa ai ngā pūtau toto whero i te ATP ko te glycolysis, e hanga ana i te hukahuka hei puna wahie matua, hei puna nui hoki.
Ko te whanaungatanga o ēnei kiko nui e rua e whakaatu ana ehara te huka i te puna "kotahi" noa iho o te pūngao, engari ko te pūtake pūngao matua mō ngā mahi nui.
7. He ngāwari te whakahaere i te hukahuka, ā, he ngāwari hoki te penapena hei glycogen.
He pūnaha homoni kua tino whanakehia e te tinana hei pupuri i ngā taumata huka toto, mā te insulin me te glucagon te nuinga. Ina piki te huka toto i muri i te kai, ka āwhina te insulin i ngā pūtau ki te mimiti i te huka me te penapena hei glycogen (i roto i te ate me ngā uaua te nuinga). Ina heke te huka toto, ka whakaoho te glucagon i te pakaru o te glycogen hei huka (i roto i te ate te nuinga) hei whakau i ngā taumata huka toto.
He mea nui te penapena i te hukahuka hei glycogen nā te mea:
– e whakarato ana i ngā rahui pūngao tere,
– tautoko i ngā hākinakina me ngā mahi ā-tinana,
– te pupuri i te nui o te huka mō te roro.
8. Ko te hukahuka anō hoki te pū o ngā ara pākia o ētahi atu.
Haunga te pūngao, ka whakaratohia hoki e te hukahuka ngā rauemi mata mō te hanga koiora. Mā roto i ngā ara maha, ka taea e te hukahuka te whai wāhi ki te hanganga o:
– ribose (mō ngā nucleotides/DNA-RNA) mā te ara pentose phosphate,
– ngā matū mua o ētahi waikawa amino,
– ngā wāhanga ngako (mā te acetyl-CoA mēnā he nui rawa te pūngao).
Ko te tikanga o tēnei, ka āwhina te hukahuka i ngā pūtau kia "ora" me te kaha, engari kia "tipu" hoki, kia whakatika i a rātou anō.
Te Katinga
He mea nui te hukahuka mō te whakaputa ATP nā te mea he wahie tere, ngāwari, me te whai hua. Ka taea e te hukahuka te whakaputa ATP mā te glycolysis ina iti te hāora, ā, ka taea e ia te whakaputa i te nui o te ATP mā te manawa ā-hauora ina rawaka te hāora. Hei tāpiri, ko te hukahuka te pūtake pūngao matua mō ngā whekau nui pērā i te roro, ā, ko te pūtake pūngao anake mō ngā toto whero, kāore he mitochondria. Nā tōna kaha ki te penapena hei glycogen me tōna whai wāhi ki ngā momo ara pākia, he mahi nui tā te hukahuka i roto i te whakahaere pūngao o te tinana.
Ki te hiahia koe, ka taea e au te whakarerekē i tēnei tuhinga hei putanga pūtaiao ake (me ngā kupu matū koiora me ngā hoahoa taahiraa-i-te-taahiraa) hei putanga rongonui ake rānei mō ngā ākonga kura waenga/kura tuarua.
