Kuyini i-stomata: izici zesakhiwo nokusebenza

Leli qembu liyingxenye engxenyeni yezitshalo, ezenza imisebenzi ebaluleke kakhulu yomoya kanye nokushintshaniswa kwegesi. Kungenzeka ukuthi ukuqaliswa kwazo kuhlotshaniswa nezici zezinto ezakhiwe yiqabunga, enye yazo yi-stomata. Ngosizo lwabo, lesi sitshalo siphefumula futhi siphume amanzi. Kuyini i-stomata, yiziphi izici zesakhiwo sabo nenhlangano, sizobe sitshele ngokuningiliziwe esihlokweni sethu.

Ukuphefumula kanye ne-photosynthesis yezitshalo

Zonke izinto eziphilayo, kuhlanganise nezitshalo, ziyakwazi ukuphefumula. Lonke iqiniso eliyaziwayo yisimo esibalulekile sokuba khona kwabo. Ingqikithi yayo ikhona ekuthandeni kwe-oksijeni, i-oxidation yezinto eziphilayo kanye nokukhululwa kwe-carbon dioxide. Kodwa ukubaluleka kwezitshalo zezitshalo kuwukuqaliswa kwenqubo eguqukayo - izithombeynthesis. Esikhathini salo, i-carbon dioxide ixhunyiwe, futhi i-oxygen, edingekayo kuzo zonke izinto eziphilayo, ikhishwa. Izimila ziyakwazi ukwenza lezi zinqubo ezimbili kanyekanye ngezinhloso ezahlukene, ikakhulukazi ngenxa yomsebenzi we-stomata ebusweni beqabunga.

Isakhiwo se-stomata

Iyini i-stomata? Lolu uhlobo lwezinambuzane, olunezicubu ezingezansi zezitshalo, okuthiwa i-peel. I-stomata yizinqamuzana ezibhanqene kakhulu ezinama-bean. Izindonga zabo azihlanganisiwe ezindaweni ezahlukene. Phakathi kwamangqamuzana e-stomata kukhona ukuqothulwa kwesisu. Ngalo, izinto ezihlukahlukene zamagesi zikhishwa zibe ngamaseli esitshalo naphandle. Amaseli kanambambili we-stomata angashintsha isimo sakhe, ngenxa yalokho ubukhulu begebe phakathi kwabo kungakhuphuka noma buyeke. Ngenxa yalokho, izinga lokushintshaniswa kwegesi esitshalweni lilawulwa.

Izici ze-stomata ukusebenza

Uma siqonda ukuthi yiyiphi i-stomata, khona-ke yilokhu abakwenzayo nokuthi kuncike kulo, sisadingeka sithole. Amaseli wokuvala akwazi ukushintsha ukuma kwawo kuye ngokuthi inani lamanzi. Uma kukhona okuningi kwalokhu kulesi sitshalo, bavuvukala, bakhulise usayizi futhi bahambe kude komunye nomunye. I-stomatal ikhala, ngokwemvelo, iyanda. Inqubo yokushintshanisa igesi iba kakhulu. Amanzi angaphezu kwamanzi ashiya igebe, aphumele, futhi isitshalo asinamandla ngesikhathi sonyaka esishisayo.

Ukuphefumula nakho kunamandla kakhulu uma izinga lokushisa lomoya likhuphuka futhi amandla emoya akhula. Esimweni esihlukile, lapho umswakama enganele, indlela yokwenziwa kwamaseli wokuvala ahlukile. Zihambisana ngokuqinile, kanti i-stomatal gap iyanyamalala kalula, okuvimbela inqubo yokungena kwamanzi. Ngenxa yalokho, lesi sitshalo asilahlekelwa umswakama ngaphansi kwezimo zokuntuleka kwayo.

Indawo ye-stomata

Njengoba sekushiwo kakade, i-stomata yizinhlaka zezicubu eziphilayo ezingezansi zezitshalo. Ibizwa ngokuthi i-peel. I-stomata yezitshalo ikhona, ezimweni eziningi, ngaphansi kweqabunga leqabunga. Lona uhlobo lokuvikelwa elangeni eliqondile. Futhi, ukugcinwa kwamanzi kumaseli esitshalo kugcinwe kangcono. Kodwa akuzona zonke amaqabunga ahlelwe ngokuzungezile. Isibonelo, zikhula ngama-irises. Ngakho-ke ama-stomata asakazwa kuzo zonke izinhlangothi zamaqabunga.

Isimo sihlukile ezitshalweni zamanzi. Ingxenye engezansi yamaqabunga awo ayikwazi ukuqukatha i-stomata. Phela, bajatshelwe ngokuphelele emanzini, ngakho-ke ngeke bakwazi ukwenza imisebenzi yabo. Isitshalo sezitshalo ezinjalo siseqenjini leqabunga. Inombolo yawo inkulu kakhulu, kusukela ku-centimeter eyodwa yesigcawu seshidi - kuze kufike ezinkulungwaneni eziningana zezinhlelo ezinjalo.

Izitshalo ngaphandle kwe-stomata

Futhi ezinye izitshalo azikho iziqu. Isibonelo, amaqabunga e-Elodee agonywa ngamanzi ngokuphelele, ngakho akakwazi ukuwafaka. Futhi noma ngabe i-stomata yayilapho, ukusebenzisa umsebenzi wabo bekungeke kwenzeke. Iphuzu eliphelele ukuthi amanzi angene emaphandleni, evimbela inqubo yokushintshaniswa kwegesi.

Ukubaluleka kwe-stomata

I-stomata itholakala emathisini angenayo, ngakho-ke umsebenzi wabo oyinhloko yi-metabolism yezinto eziphilayo nemvelo. Omunye wabo ngamanzi, inqubo yokuchithwa okubizwa ngokuthi ukuphefumula. Ukusetshenziswa kwalo kubaluleke kakhulu ukuze izitshalo zingapheli ngesikhathi sishisa, ngoba lokhu kungaholela ekufeni kwabo. Uma ukuvuthwa kungathandeki, i-stomata cishe igweme ukuphefumula, ngaleyo ndlela igcine umswakama obalulekile.

Kodwa i-gymnosperms inesidingo esikhethekile se-stomata. Zivaliwe phakathi nobusika ne-resin ekhethekile. Ngakho-ke, bonke abamele lo mnyango wezitshalo bahlale bevundlile. Akudingeki ukuba balahle amahlamvu ukuzivikela ekulahlekelweni komswakama ngokweqile ebusika. Ngokungafani nabo, wonke ama-Angiosperms agcina asebenza kahle futhi aphunyuke kuphela kule nkathi. Kodwa amaqabunga awo awe, ukuze angalahlekelwa amanzi ebusika. Ngakho-ke, i-herringbone "ebusika nasehlobo ngombala owodwa."

Yini ehlelwe, ukuthi ihlelwe kanjani futhi ifeze imisebenzi yayo, sibheke ngokuningiliziwe. Kodwa-ke, kufanele futhi kuthiwe, ngaphandle kokuphefumula, futhi bakhonza njengezici ezikhethekile zokuhlinzeka nge-oksijini, ukuze inqubo yokuphefumula kanye ne-carbon dioxide ithole i-photosynthesis inokwenzeka. Ngaphezu kwalokho, i-stomata ingakwazi ukulawula ukuqina kwazo zonke lezi zinqubo, ezixhomeke ezintweni zangaphandle, futhi zibonakalise ekukwazi ukuvumelanisa zonke izinto eziphilayo ukuze zishintshe ngokushesha izimo zemvelo.

Ngakho-ke, ezinxenyeni ezingenalutho zeqabunga kunezinhlobo ezikhethekile, ezibizwa ngokuthi i-stomata. Ziqukethe amaseli wokuvala kanambambili kanye negebe phakathi kwabo. Ngenxa yomsebenzi walolu sakhiwo, izinqubo ezibaluleke kakhulu zokuphuma kwamanzi, i-photosynthesis nokuphefumula zenziwa emzimbeni wesitshalo.