I-trachea ithwala umoya ngaphakathi esifubeni, apho ihlula khona ngamasebe amancinci amancinci (i-bronchi) ehambisa umoya kumaphaphu. I-Bifurcating, i-bronchi yenza inqubo yokunciphisa imizimba ye-tubules ize ifike kuzo zonke iindawo zomphunga. Ziphela kunye nezikhwama ze-alveolar ezincane, apho izicubu zomphunga ziquka. Kule mibhobho enobumba obunqabileyo obunokutshintshiselana kwegesi kwenzeka phakathi kwomoya ophefumlelweyo kunye negazi. Iphepha eliphambili nelingaphantsi lokuphefumula liyintloko yesihloko.
Trachea
I-trachea iqala kwi-cartilage yecricoid, ephantsi nje kwe-larynx, kwaye ihla emgodini wesifuba. Kwinqanaba le-sternum, i-trachea iphelile, ihlula ngamasebe amabini-i-bronchi ephezulu nekhohlo. I-Trachea iqukethe i-fibroelastic tissue eqinile kunye neketingi leemali ezingavaliweyo ze-hyaline cartilage (i-cartilage ye-trachea). I-trachea yomntu omdala inele (malunga no-2.5 cm ububanzi), ngelixa abantwana bebancinci (malunga nepensile ububanzi). Ingxenye engezantsi yenkqubo ye-trachea ayinayo inkxaso yokuxhamla. Iqukethe imizimba yefiber and muscle fibers. Le nxalenye yecandelo le-trachea lixhomekeke kwisigxina esisemva kwayo ngqo. I-trachea kwicandelo eliphambene nendawo evulekile. I-epithelium (i-lining yangaphakathi) ye-trachea iqukethe iiseli ze-goblet ezifake i-mucus kumphezulu, kunye ne-microscopic cilia, leyo, ngokuhambelana okuhambayo, iwabambe iincinci zothuli kwaye iwaphephe emiphakeni ukuya kwi-larynx. Phakathi kwe-epithelium kunye neengqungquthela ze-cartilaginous ingxube yeethambo ezixubileyo ezinezixhobo ezincinci zegazi kunye neelymph, neentsholongwane kunye neengqungquthela ezivelisa i-mucus yamanzi kwi-lumen ye-trachea. Kwi-trachea, kukho neenamba ze-elastic fibers ezinika ukuguquguquka. I-bronchus eqhubekayo isebenza kwisebe, eyenza okuthiwa umthi onqabileyo, ithwala umoya kuwo onke amaphepha. Ngokuyinhloko i-bronchus eyintloko ihlukaniswe ibe yi-lobar bronchi, emithathu emgangathweni olungileyo, kunye neyesibini kumphunga wekhohlo. Ngamnye wabo uhambisa umoya kwi-lobes yomphunga. I-lobar bronchi yahlulwa ibe yincinci leyo eyenzela umoya ukuhlukanisa iziteshi.
Ulwakhiwo lwebronchi
Isakhiwo se-bronchi sifana nesakhiwo se-trachea. Zincinci kwaye ziguquguquke, iindonga zazo ziqulethe i-cartilage, kwaye umphezulu uhlanganiswe ne-epithelium yokuphefumula. Kananjalo banemibala eyahlukahlukeneyo yemisipha, eqinisekisa ukuba utshintsho bububanzi bayo.
Bronchioli
Ngaphakathi kwamacandelo e-bronchopulmonary, i-bronchi iyaqhubeka isebe. Ngomhla ngamnye we-branching, i-bronchi ibe yincinci, kwaye inxalenye yecandelo elinqamlezileyo likhula. I-Bronchi, eneesalathisi sangaphakathi ngaphantsi kwe-1 mm, kuthiwa yi-bronchioles. Ukususela kwiibhubhu ezinkulu ze-bronchial, i-bronchioles ihluke kwiindonga zabo aziqukethe i-cartilage kunye neeseli ezinqamlekileyo kwizitha zangaphakathi. Nangona kunjalo, kunye ne-bronchi, baneemfibisi ze-muscle. Ukugqithiswa okuqhubekayo kubangela ukubunjwa kwe-bronchioles yesigxina, ekwahlukana, ibe yinto encinci ye-bronchioles yokuphefumula. I-bronchioles evuthayo ibizwa ngokuba ngenxa yokuxubana ngqo ne-lumen ye-alveoli ethile. Nangona kunjalo, bashiya amaqhekeza ukusuka kumanqwanqwa e-alveolar, ukuxhuma kwi-bronchioles yokuphefumula.
Alveoli
I-Alveoli iisanti ezincinane ezingenanto kunye neendonga ezincinci kakhulu. Ukutshintshiselwa kweGesi kubonakala kuzo. Kungenxa yeendonga ze-alveoli ukuba i-oksijeni evela emoyeni oxinyiweyo ingena kwi-pulmonary circulation through dissemination, kunye nemveliso yokugqibela yokuphefumula, i-carbon dioxide, ikhishwa ngaphandle ngaphandle kwomoya okhupha umoya. Imiphunga yomntu iqulethe izigidi ze-alveoli, ezidibeneyo zenza ummandla omkhulu (malunga ne-140 m2), eyaneleyo yokutshintshwa kwegesi. Iifomathi zeAlveoli zifana neziqhamo zamagilebhisi, ezijikelezileyo kwizifundo ze-alveolar. I-alveolus ngayinye ine-lumen encinci evula kwi-alveolar course. Ukongezelela, kukho izimbobo ezincinci (pores) kumgangatho we-alveolus nganye, apho idibana ne-alveoli engumakhelwane. Iindonga zazo zidibene ne-epithelium eplatili. I-alveoli iqulethe ezimbini iintlobo zeeseli: ii-macrophages (iiseli ezikhuselekileyo), iintlobo zangaphandle ezingena emaphaphu ngokusebenzisa umthambo wokuphefumula, kunye neeseli ezivelisa i-surfactant-ibalulekileyo yezinto eziphilayo.