Phloem - Iyini? Umsebenzi, isakhiwo phloem, xylem Ngokungafani

Phloem - uhlobo olukhethekile kwezicubu isitshalo. Olimini esiGrekini nkulumo isho ukuthi "namagxolo". Njengoba uvame ukubizwa kanjalo phloem. Phloem - indwangu lapho ukudluliswa kwezakhi ezithweni isitshalo. Kuyini isakhiwo kuba? Injani ezokuthutha izakhi? Yini lihlukile xylem?

Ukuqhuba izicubu izitshalo: xylem futhi phloem

Ukuze ezokuthutha amaminerali kanye namanzi ukuze izingxenye ezahlukene isitshalo ezidingekayo Indwangu conductive. Siqukethe ezimbili izinhlobo kwezicubu eziyinkimbinkimbi - phloem futhi xylem.

Xylitol futhi ngokuthi ukhuni phloem - kunjalo. Zivame elise iseduze nomunye bese bakha imishayo conductive (obizwa nangokuthi fibrous semithambo). Ngu ilungiselelo mutual xylem futhi phloem ezishisa kakhulu zikhipha izinhlayiyana izinhlobo eziningana izindwangu conductive:

1. Kollaterialnye (izicubu eduze komunye nomunye futhi etholakala equidistant kusukela ingxenye Axial yomzimba isitshalo).
2. Bikollaterialnye (xylem sizungezwe phloem izingxenye ezimbili).
3. Eyindilinga (lapho xylem izungeza phloem kanye noHezekeli).
4. Groove (lapho phloem futhi xylem ka engaba kwenzeka block game).

Isakhiwo phloem

isitshalo phloem - uhlobo olukhethekile Indwangu conductive, okuyinto edingekayo ukuze adlulisele umsoco, kwakheka ngenxa ye-photosynthesis, ukuze izitho zalesi sihlahla, lapho zisetshenziselwa bona. Ngu uhlobo imvelaphi sehlukaniswe lezi zinhlobo ezilandelayo:

• oyinhloko (umehluko procambium);
• yesibili (kumiswa cambium).

umehluko lawo eliyinhloko ukuthi phloem eyinhloko lingekho tube amise okwenhliziyo. Nokho, ukwakheka kwamangqamuzana yabo nsé.

Phloem siqukethe iseli zinhlobo ezilandelayo:

• ngesihlungo (ukunikeza ukudluliswa eyinhloko ejenti futhi abanalo nuclei cell);
• sclerenchyma (ukukhonza ukusekela);
• parenchymal (umsebenzi njengoba ongaphakeme osabalalayo ezokuthutha).

Isici esiyinhloko amaseli ngesihlungo - khona ikhule ezimbotsheni ekhethekile izindonga cell. umsuka wabo ibingakazeki. I zeziteshi uphahlwe callose ngesihlungo izakhi (polysaccharide), okungaba buthelela kubo. Callose kungase occlude iziteshi sezitokisi, isibonelo, lapho sitshalo endaweni esigabeni yokuphumula ebusika.

ezokuthutha phloem

Phloem - indwangu, okuyinto bashukunyiswa izixazululo kanzulu of hydrocarbon (ikakhulukazi sucrose) kwakheka ngenxa ye-photosynthesis. Ngaphezu kwalokho, idluliselwe assimilates futhi metabolites, kodwa at lokuhlala aphansi. mass ukudluliswa izinga ifinyelela amashumi amaningana amasentimitha ngehora.

Kudluliswa izinto Kwenziwa yizinhlaka lapho izakhi ngenkuthalo kwakhiwa, ukuba izingxenye izitshalo, lapho esetshenziselwa noma Stocking. izinto ezisebenzayo zidluliselwa izimpande, amahlumela, amahlamvu abasafufusa, Izitho zokuzala, nezilimo eziyizigaxa, ama, rhizomes.

Ngenxa yalokho zokuhlolwa, abacwaningi bathola ukuthi ukuthuthwa Kwenziwa donor ejensi kulabo izingxenye izitshalo nabo. Ngaphezu kwalokho, ukudluliselwa izinto kuyinto zamazwe amabili. Ngakho-ke, lesi sitshalo ezinkathini ezihlukahlukene yokukhula zinganqwabelana izakhi noma ukuchitha kubo.

Phloem: umsebenzi

Photosynthesis kwenzeka chloroplast amaqabunga, iqhaza elangeni. imikhiqizo yayo, amanzi kanye nezinye izixazululo amaminerali amuncwa izimpande zezitshalo kuyadingeka ukusebenza wonke amaseli. Phloem - yindwangu enikeza translocation yabo. ukugeleza nosimende izakhi ngesihlungo kusuka izindawo ophezulu hydrostatic ezindaweni ngokujulile ukubaluleka kwaso ongaphakeme. Ngakho-ke, umsebenzi oyinhloko phloem - ezokuthutha.

Ngokungafani xylem kusukela phloem

Naphezu kweqiniso lokuthi xylem futhi phloem kwenza imisebenzi efana futhi isondelene, banayo umehluko. Ukuhambisa e xylem izinto ethathwe empandeni kuya amahlamvu. Ngaphezu kwalokho, amangqamuzana akha lolu hlobo Indwangu kukhona izakhi semithambo, tracheids, zemicu ukhuni parenchyma. Xylem kuyadingeka zokudlulisela amanzi kanye nezakhi yahlakazeka.

Ngakho phloem - uhlobo izicubu semithambo zalesi sihlahla. It ukhonza ukudlulisa nezakhi izitho zalesi sihlahla, lapho bakha asebenzayo kulezo izingxenye lapho agodliwe noma kudliwe. Phloem lakhiwe ngemalunga lamatsatfu zamangqamuzana - ngesihlungo, sclerenchyma futhi parenchymal. The main yezokuthutha umsebenzi ngesihlungo amaseli bahlinza ikhule ezimbotsheni ekhethekile abangenalo nuclei.

Ukudluliswa izinto kungaba kwenziwe ngezindlela ezimbili, futhi ngezinye izikhathi ijubane layo uma igijima ifinyelela amashumi amaningana amasentimitha ngehora. Enye indwangu conductive, ezifanayo umsebenzi kuya phloem, xylem kuyinto. Kodwa umehluko yabo eyinhloko itholakala lokuthi ukuthi xylem uyisa isiqondiso eyodwa kuphela (kusuka izimpande amahlumela) amanzi amaminerali siphela.