Ntchito ya Myoglobin mu Kusungirako Mpweya wa Oxygen mu Minofu
Myoglobin ndi puloteni yofunika kwambiri m'thupi la munthu ndi nyama, makamaka yokhudzana ndi kuthekera kwa minofu kugwira ntchito bwino. Puloteni iyi imadziwika kuti "chosungira mpweya" m'minofu ya minofu. Ntchito yake imakhala yofunika kwambiri pamene minofu imafuna mphamvu zambiri, monga panthawi yochita masewera olimbitsa thupi , kuthamanga, kusambira, kapena kuchita masewera olimbitsa thupi ena. Kuti timvetse chifukwa chake myoglobin ndi yofunika kwambiri, tiyenera kumvetsetsa kuti ndi chiyani, kapangidwe kake, momwe imasungira mpweya, komanso ubale wake ndi magwiridwe antchito a minofu ndi matenda ena.
Kodi myoglobin ndi chiyani?
Myoglobin ndi puloteni yozungulira yomwe imapezeka m'maselo a minofu , makamaka mafupa ndi minofu ya mtima. Myoglobin imathandizira kwambiri kuti mtundu wofiira wa nyama ndi minofu ukhale wofiira, zomwe zimapangitsa kuti nyama yokhala ndi myoglobin yambiri (monga ng'ombe) iwoneke yofiira kwambiri kuposa nyama yokhala ndi myoglobin yochepa.
Mwa ntchito yake, ntchito yaikulu ya myoglobin ndikugwirizanitsa mpweya ndikuusunga m'maselo a minofu. Mpweya uwu umatha kutulutsidwa pamene minofu ikufuna mphamvu ndipo magazi sakwanira kukwaniritsa zosowa zachangu.
Kapangidwe ka myoglobin ndi ubale wake ndi ntchito yake
Myoglobin imapangidwa ndi unyolo umodzi wa polypeptide (mosiyana ndi hemoglobin, womwe uli ndi ma subunits anayi). Kapangidwe kake ka magawo atatu kamalola myoglobin kupanga "thumba" lapadera lomwe lingathe kumangirira mamolekyu a okosijeni. Chinsinsi cha luso limeneli ndi kukhalapo kwa gulu la heme—kapangidwe kake kamene kali ndi chitsulo (Fe) pakati pake. Chitsulochi chimamangirira mwachindunji ku okosijeni.
Popeza ili ndi gawo limodzi lokha, myoglobin ili ndi makhalidwe osiyana omangirira mpweya poyerekeza ndi hemoglobin. Myoglobin ili ndi mphamvu ya mpweya wambiri kuposa hemoglobin. Izi ndizomveka: hemoglobin imanyamula mpweya kudzera m'magazi ndipo iyenera kuutulutsa mosavuta kupita ku minofu, pomwe ntchito ya myoglobin ndi "kusunga" mpweya ngati malo osungira minofu ndikuutulutsa pokhapokha ngati pakufunika kutero.
Njira yosungira mpweya m'minofu
Mpweya umene timapuma umalowa m'mapapo, komwe umalumikizana ndi hemoglobin m'maselo ofiira a magazi ndipo umatengedwa m'thupi lonse kudzera m'mitsempha yamagazi. Magazi akafika m'minofu ya minofu, mpweya umatulutsidwa ndipo umafalikira m'maselo a minofu. Apa ndi pomwe myoglobin imagwira ntchito yofunika kwambiri: imamanga ndikusunga mpweya.
Kusunga mpweya m'thupi kuli ndi ubwino wambiri:
1. Mpweya wosungidwa ukawonjezeka mwadzidzidzi pamene kufunika kwake kukuwonjezeka
Minofu ikagwira ntchito molimbika mwadzidzidzi, kufunika kwa mpweya kuti upange mphamvu kumawonjezeka mofulumira kwambiri. Myoglobin imapereka mpweya wosungira nthawi yomweyo isanayambe. dongosolo la kupuma ndi Kuzungulira kwa magazi kumatha kusintha ndikuwonjezera mpweya wochokera m'mapapo.
2. Zimathandiza kufalikira kwa mpweya m'maselo a minofu
Myoglobin imathandiza "kutumiza" mpweya kuchokera pamwamba pa selo kupita ku mitochondria, komwe kupanga mphamvu Mwa kuyankhula kwina, myoglobin imathandizira kufalitsa mpweya m'maselo a minofu.
3. Zimathandiza kuti kagayidwe kachakudya m'thupi kasamayende bwino
Kupanga mphamvu kudzera mu njira ya aerobic kumakhala kothandiza kwambiri kuposa njira ya anaerobic. Kupezeka kwa myoglobin kumalola minofu kukhalabe mu mkhalidwe wa aerobic kwa nthawi yayitali isanayambe kugwiritsa ntchito njira za anaerobic zomwe zimapanga lactic acid.
Udindo wa myoglobin mu masewera olimbitsa thupi ndi masewera
Tikamachita masewera olimbitsa thupi kwambiri, matupi athu amafuna mphamvu zambiri. Mphamvu imeneyi imapangidwa makamaka mu mitochondria kudzera mu okosijeni wa michere (shuga ndi mafuta) mothandizidwa ndi mpweya. Myoglobin imagwira ntchito yofunika kwambiri poonetsetsa kuti mpweya umapezeka nthawi zonse.
Mu gawo loyamba la masewera olimbitsa thupi, myoglobin imatulutsa mpweya mwachangu kuti ikwaniritse kufunikira kwa minofu. Izi zimathandiza kuchepetsa "kusowa kwa mpweya" koyambirira. Myoglobin ikachuluka mu minofu, imakhalanso ndi mphamvu yabwino yosungira mpweya ndikugwira ntchito kwa nthawi yayitali popanda kutopa.
Izi zikufotokozanso chifukwa chake othamanga opirira, monga othamanga mtunda wautali kapena osambira, amakonda kusintha thupi lawo mwa kuwonjezera mphamvu ya okosijeni ku minofu, kuphatikizapo kuchuluka kwa mitochondria ndi mapuloteni ofunikira monga myoglobin kudzera mu maphunziro okhazikika.
Myoglobin mu nyama zodumphira m'madzi ndi kusintha kwakukulu
Chimodzi mwa zitsanzo zosangalatsa kwambiri za ntchito ya myoglobin chikuwoneka m'zilombo zosambira pansi pa madzi monga anamgumi, zisindikizo, ndi ma dolphin. Zinyama izi zimatha kusambira pansi pa madzi kwa nthawi yayitali popanda kupuma. Chimodzi mwa zinsinsi zawo chili mu kuchuluka kwa myoglobin m'minofu yawo. Kuchuluka kwa myoglobin kumeneku kumalola minofu yawo kusunga mpweya wambiri wosungira, zomwe zimawathandiza kuti aziyendabe ndikukhalabe pansi pa madzi popanda mpweya wochokera mumlengalenga.
Ndipotu, m'mitundu ina, kuchuluka kwa myoglobin kumakhala kwakukulu kwambiri kotero kuti minofu imawoneka yakuda kwambiri. Kuwonjezera pa kuchuluka kwake kwakukulu, myoglobin m'zinyama zosambira ilinso ndi zinthu zapadera zomwe zimachepetsa chizolowezi cha mapuloteni awa kusonkhana pamlingo waukulu, zomwe zimawalola kukhalabe olimba ndikugwira ntchito bwino.
Kusiyana pakati pa myoglobin ndi hemoglobin
Ngakhale kuti zonse ziwiri zimamangirira mpweya ndipo zonse zimakhala ndi heme, myoglobin ndi hemoglobin zimagwira ntchito zosiyanasiyana:
– Hemoglobin: imapezeka m'maselo ofiira a magazi, imagwira ntchito yonyamula mpweya kuchokera m'mapapo kupita ku minofu ndikunyamula mpweya wa carbon dioxide kubwerera m'mapapo. Ili ndi magawo anayi ang'onoang'ono kotero imatha kumangirira mamolekyu anayi a mpweya.
– Myoglobin: imapezeka m'maselo a minofu, imagwira ntchito yosungira mpweya ndikuthandizira kufalikira kwake mu mitochondria. Ili ndi gawo limodzi lokha ndipo imamanga molekyulu imodzi ya mpweya.
Kuphatikiza apo, hemoglobin ili ndi mphamvu zomangira mogwirizana, zomwe zikutanthauza kuti kumangirira kwa mpweya umodzi kumathandiza kumangirira kwa mpweya wina. Myoglobin ilibe mphamvu zomangira mogwirizana; imalumikiza mpweya mokhazikika, mogwirizana ndi ntchito yake ngati malo osungira.
Myoglobin ndi thanzi
Myoglobin ndi yofunika kwambiri pankhani zachipatala. Minofu ikawonongeka kwambiri, mwachitsanzo chifukwa cha kuvulala kwakukulu, ngozi, kapena matenda monga rhabdomyolysis, myoglobin imatha kutuluka m'maselo a minofu kupita m'magazi. Kuchuluka kwa myoglobin m'magazi kumatha kulowa mu impso ndikuyambitsa vuto la impso.
Mu ntchito zachipatala, kupezeka kwa myoglobin (kapena zinthu zochokera m'thupi mwake) mu mkodzo kungayambitse mdima, monga tiyi kapena cola. Ichi ndi chizindikiro chochenjeza cha kuwonongeka kwakukulu kwa minofu. Kuphatikiza apo, pakakhala vuto la mtima, myoglobin imathanso kukwera chifukwa cha kuwonongeka kwa minofu ya mtima, ngakhale kuti zizindikiro zina za mtima (monga troponin) tsopano zimagwiritsidwa ntchito kwambiri.
Mapeto
Myoglobin ndi puloteni ya minofu yomwe imagwira ntchito yofunika kwambiri pakusunga ndikupereka mpweya ku maselo a minofu. Chifukwa cha mpweya wake wambiri, myoglobin imatha kumangirira mpweya wochokera ku hemoglobin ndikuusunga ngati malo osungira. Malo osungira awa ndi othandiza pamene minofu ikufunika mphamvu mwadzidzidzi kapena pamene mpweya wochokera m'magazi sukugwirizana ndi zosowa za ntchito. Kuwonjezera pa ntchito yake yosungira, myoglobin imathandizanso kuti mpweya ulowe mu mitochondria, zomwe zimathandiza kuti kagayidwe ka aerobic kagwire ntchito bwino kwambiri.
Udindo wa myoglobin umaonekera bwino m'masewera, kusintha kwa nyama zodumphira m'madzi, komanso m'zamankhwala monga chizindikiro cha kuwonongeka kwa minofu. Pomvetsetsa ntchito ya myoglobin, titha kumvetsetsa bwino momwe thupi limayendetsera bwino mpweya kuti lithandizire kuyenda, kupirira, komanso thanzi la minofu yonse.
