Izithobezi ezenza kuqala zikhona emlonyeni - izigqoko eziyinkimbinkimbi. I-saliva eyenziwa yizici zine-enzyme eqala ukugaya isitashi kusuka kokudla ibe ama-molecule amancane.
Isethi esilandelayo yezigulane zokugaya isisu sokugaya. Bakhiqiza i-acid esiswini kanye ne-enzyme egaxa amaprotheni. Enye yamaphazidi angaxazulwanga wesimiso sokugaya umzimba yingakho ijusi le-asidi yesisu alichithi izicubu zesisu ngokwazo.
Kubantu abaningi, i-mucosa yesisu iyakwazi ukumelana nomusi, nakuba ukudla nezinye izicubu zomzimba akunakwenzeka.
Ngemuva kokuba isisu sikhipha ingxube yokudla kanye nejusi emathunjini amancane, ama-juice nezinye izitho ezimbili zokugaya zihlanganisa nokudla ukuqhubeka nenqubo yokugaya. Elinye lala malungu yi-pancreas. Iveza ijusi eliqukethe izinhlobo eziningi ze-enzyme ukuze kuphulwe ama-carbohydrate, amafutha, namaprotheni ekudleni. Amanye ama-enzyme asebenzayo kule nqubo aphuma ezigodini ezisodongeni lwamathumbu noma ngisho nenye ingxenye yalolu donga.
Isibindi sikhiqiza elinye ijusi lokugaya - bile. I-bile igcinwa phakathi kokudla ku-gallbladder. Ngesikhathi sokudla, kukhishwa ngaphandle kwe-gallbladder kuya emathangeni e-bile ukuze kufinyelele emathunjini futhi uhlanganise namafutha ekudleni kwethu. I-bile yenza uhlaka lwamafutha luhlakaze emathunjini, njengama-detergents anqamula amafutha avela epanini lokuthosa.
Ngemuva kokuba amafutha aqothulwa, ahlushwa ama-enzyme avela ku-pancreas kanye nasezindlini zamathumbu.
Yini Elawula Inqubo Yokugaya?
Abalawuli beHormone
Isici esithakazelisayo se-digestive system ukuthi iqukethe izilawuli zayo. Ama-hormone amakhulu alawula imisebenzi yesimiso sokugaya umzimba akhiqizwa futhi akhululwe ngamaseli e-mucosa wesisu nesisu somncane.
Lawa mahomoni adedelwa egazini legciwane lokugaya, abuyele enhliziyweni nangemithambo yegazi, aphinde abuyele ohlelweni lokugaya, lapho evuselela khona amajusi okugaya futhi abangele ukuhamba komzimba.
Amahomoni alawula ukugaya yi-gastrin, secretin, ne-cholecystokinin (CCK):
- I-Gastrin ibangela isisu ukuba sikhiqize i-asidi yokuqeda nokugaya ukudla okunye. Kubuye kudingekile ukukhula okujwayelekile kwendlala yesisu, intathuzane encane, kanye ne-colon.
- I-Secretin ibangela ukuthi ama-pancreas athumele ijusi lokugaya elicebile ku-bicarbonate. Ivuselela isisu ukuba kuvezwe i-pepsin, i-enzyme eyenza amaprotheni, futhi ivuse isibindi ukuba ikhiqize i-bile.
- I-CCK ibangela ukuthi ama-pancreas akhule futhi akhiqize ama-enzyme wejusi le-pancreatic, futhi kubangela ukuthi i-gallbladder ingabi nalutho.
Amahomoni engeziwe e-system yokugaya ukudla alawula ukudla:
- I-Ghrelin ikhiqizwa esiswini nasemathunjini aphezulu ngokungabi khona kokudla ohlelweni lokugaya umzimba futhi kukhuthaza ukudla.
- I-Peptide YY ikhiqizwa ipheshana le-GI ekuphenduleni kokudla ohlelweni futhi livimbela ukudla.
Zombili lezi amahomoni zisebenza ebuchosheni ukusiza ukulawula ukudla kwamandla.
Abalawuli Bamagciwane
Izinhlobo ezimbili zezinzwa zisiza ukulawula isenzo se-digestive system.
Izindebe ze-Extrinsic (zangaphandle) ziza ezithombeni zokugaya ezivela engxenyeni engazi lutho ebuchosheni noma emthonjeni womgogodla. Bakhulula ikhemikhali okuthiwa i-acetylcholine nomunye okuthiwa i-adrenaline. I-Acetylcholine ibangela ukuthi imisipha yezingxenye zokugaya ifinyelele ngamandla futhi yandise i- "push" yokudla nejusi ngokusebenzisa i-digestive tract. I-Acetylcholine nayo ibangela ukuthi isisu ne-pancreas zikhiqize ijusi eliningi lokugaya. I-Adrenaline ivuselela isidumbu sesisu nesisu futhi inciphise ukugeleza kwegazi kulezi zitho.
Okubaluleke nakakhulu, kodwa-ke, izinzwa zangaphakathi (zangaphakathi), ezakha inethiwekhi enesisindo esenezungezile ezindongeni zesisu, isisu, intathuzane encane, ne-colon.
Izinzwa zangaphakathi zenziwa ukuba zenze lapho izindonga zamalungu angenalutho zihanjiswe ngokudla. Bakhulula izinto eziningi ezehlukene ezisheshisa noma ezilibale ukuhamba kokudla kanye nokukhiqizwa kwamanzi ngamalungu okugaya.