Indima Yesistimu Yokujikeleza Kwegazi Ekuthuthweni Nasekushintshisaneni Kwezinto
Uhlelo lokujikeleza kwegazi lungenye yezinhlelo ezibaluleke kakhulu emzimbeni womuntu, olunesibopho sokuthuthwa nokushintshaniswa kwezinto ezibalulekile ezidingwa amaseli omzimba. Lolu hlelo alubandakanyi inhliziyo kuphela njengesitho esimpompayo, kodwa futhi nemithambo yegazi negazi njengezingxenye eziyinhloko ezijikeleza izakhamzimba, umoya-mpilo, kanye nemikhiqizo ye-metabolic. Kulesi sihloko, sizohlola ukuthi uhlelo lokujikeleza kwegazi ludlala kanjani indima ebalulekile ekusebenzeni kahle komzimba nokunempilo.
Imisebenzi Eyinhloko Yohlelo Lokujikeleza Kwegazi
Uhlelo lokujikeleza kwegazi lunesibopho sokuqinisekisa ukuthi zonke izicubu nezitho zomzimba zithola igazi elanele. Lokhu kubalulekile ngoba igazi lithwala umoya-mpilo nezakhamzimba liye emangqamuzaneni ngesikhathi esifanayo lisusa imfucuza efana ne-carbon dioxide ukuze ilahlwe.
1. Ukuthuthwa kwe-Oxygen ne-Carbon Dioxide:
Inhliziyo ipompa igazi ngezinhlelo ezimbili eziyinhloko zokujikeleza kwegazi: ukujikeleza kwegazi okujwayelekile kanye nokujikeleza kwamaphaphu. Ekujikelezeni kwamaphaphu, igazi elingenawo umoya-mpilo liyapompa lisuka enhliziyweni liye emaphaphu. Emaphaphu, igazi likhipha i-carbon dioxide bese lithola umoya-mpilo ngaphambi kokuba libuyele enhliziyweni. Bese kuthi, ngokujikeleza kwegazi okujwayelekile, igazi elinomoya-mpilo lipompelwe kuwo wonke umzimba ukuze lisetshenziswe amaseli.
2. Ukulethwa Kwezakhamzimba Nama-hormone:
Ngaphezu komoya-mpilo, igazi liphinde lithwale izakhamzimba ezivela emgudwini wokugaya ukudla ziye emangqamuzaneni emzimbeni wonke. Lolu hlelo luphinde ludlale indima ekulethweni kwama-hormone akhiqizwa yizindlala ze-endocrine, ezilawula imisebenzi eyahlukahlukene yomzimba njengokukhula, i-metabolism, kanye nemizwa.
3. Ukulawulwa Kokushisa Komzimba:
Uhlelo lokujikeleza kwegazi lusiza ekulawuleni izinga lokushisa lomzimba ngokujikeleza igazi eduze kwesikhumba lapho umzimba udinga ukukhipha ukushisa, noma ukuligcina lijule emzimbeni lapho kudingeka ukufudumala.
4. Ukuvikelwa Nokuphulukiswa Kwenxeba:
Izingxenye zegazi ezifana namaseli amhlophe egazi ziyingxenye yesimiso somzimba sokuzivikela, zivikela umzimba ekuthelelekeni. Ngaphezu kwalokho, ama-platelet adlala indima ebalulekile enkambisweni yokujiya kwegazi, evimbela ukulahleka kwegazi ngokweqile ngesikhathi sokulimala.
Izingxenye Eziyinhloko Zesistimu Yokujikeleza Kwegazi
1. Inhliziyo:
Inhliziyo iyisitho esiyinhloko ohlelweni lokujikeleza kwegazi lomuntu. Inamakamelo amane: i-atria amabili kanye nama-ventricle amabili. Umsebenzi oyinhloko wenhliziyo ukupompa igazi liye emaphashini ukuze kutholakale umoya-mpilo, bese lipompa leli gazi elinomoya-mpilo emzimbeni wonke.
2. Imithambo yegazi:
Kunezinhlobo ezintathu zemithambo yegazi: imithambo yegazi, imithambo yegazi, kanye nama-capillary. Imithambo yegazi ithwala igazi isuka enhliziyweni emzimbeni wonke, imithambo yegazi ithwala igazi ibuyele enhliziyweni, kanti ama-capillary yilapho kwenzeka khona ukushintshana kwezinto phakathi kwegazi namaseli.
3. Igazi:
Igazi lakhiwe yizingxenye eziningana: amangqamuzana abomvu egazi athwala umoya-mpilo, amangqamuzana amhlophe egazi asebenza ohlelweni lokuzivikela komzimba, ama-platelet adlala indima ekujiyeni kwegazi, kanye ne-plasma ethwala izakhamzimba, ama-hormone, namanye amaprotheni abalulekile.
Indlela Yokushintshana Kwezidakamizwa
Ukushintshana kwezinto kwenzeka ikakhulukazi kuma-capillary, imithambo yegazi emincane kakhulu enezindonga ezincane kakhulu ezivumela ukushintshana kwamagesi, izakhamzimba, kanye nemikhiqizo engcolile phakathi kwegazi nezicubu zomzimba. Le nqubo yenzeka ngezindlela eziningana:
1. Ukusabalala: Izinto zihamba zisuka ezindaweni ezigcwele kakhulu ziye ezindaweni ezigcwele kakhulu. Isibonelo, igazi elinomoya-mpilo lizosabalala liye ezicutshini lapho izinga lomoya-mpilo liphansi khona.
2. Ukuhlunga kanye ne-Osmosis: Uketshezi luhamba odongeni lwe-capillary ngenxa yokucindezela koketshezi kanye nokwehluka kokuhlushwa kwe-solute (osmosis), okubalulekile ekugcineni ibhalansi yoketshezi phakathi kwegazi nezicubu.
3. Ukuthuthwa Okusebenzayo: Ezinye izinto ezifana ne-glucose nama-ion athile zingadinga amandla ukuze zihambe ngaphesheya kwe-membrane yeseli, noma ngabe zihamba ngokumelene ne-gradient yokuhlushwa.
Ukubaluleka Kwesistimu Yokujikeleza Kwegazi Enempilo
Uhlelo lokujikeleza kwegazi olunempilo lubalulekile ekusebenzeni kahle komzimba. Izifo zenhliziyo, ezibangelwa umonakalo noma ukungasebenzi kahle kwalolu hlelo, ziyimbangela ehamba phambili yokufa emhlabeni jikelele. Umfutho wegazi ophakeme (umfutho wegazi ophakeme), i-atherosclerosis (ukunqwabelana kwama-plaque emithanjeni), kanye ne-myocardial infarction (ukuhlaselwa yinhliziyo) ngezinye zezimo ezingaphazamisa kakhulu ukusebenza kohlelo lokujikeleza kwegazi.
Ukuze ulondoloze uhlelo lokujikeleza kwegazi olunempilo, kubalulekile ukulandela indlela yokuphila enempilo, njengokudla ukudla okunomsoco, ukuzivocavoca njalo, ukugwema ukubhema, nokulawula ukucindezeleka. Lezi zinyathelo zingasiza ekugcineni impilo yenhliziyo nemithambo yegazi iphilile futhi ziqinisekise ukulethwa kahle komoya-mpilo nezakhamzimba emzimbeni wonke.
Isiphetho
Uhlelo lokujikeleza kwegazi ludlala indima ebalulekile ekuthuthweni nasekushintsheni kwezinto emzimbeni womuntu. Ngokuqinisekisa ukulethwa komoya-mpilo nezakhamzimba emzimbeni wonke kanye nokususwa kwemfucuza ye-metabolic ohlelweni lokukhipha ukungcola, lolu hlelo lusekela impilo kanye nempilo iyonke. Ngakho-ke, ukuqonda nokunakekela uhlelo lokujikeleza kwegazi kuyitshalomali ebalulekile empilweni yomuntu kanye nekhwalithi yokuphila. Ngokunakekelwa okufanele, okuhlanganisa indlela yokuphila enempilo kanye nokuzivocavoca umzimba njalo, lolu hlelo lungaqhubeka nokusebenza kahle empilweni yethu yonke.
