Phloem - yintoni na le nto? Umsebenzi, isakhiwo phloem, xylem Ngokungafaniyo

Phloem - luhlobo elikhethekileyo esiqwini sesityalo. Ngolwimi ngesiGrike eli gama lithetha "ixolo". Njengoko kudla ngokuba phloem. Phloem - eli laphu apho ukutshintshwa izondlo ukuba amalungu izityalo. Yintoni na isakhiwo yalo? Njani na zothutho kwezondlo? Yintoni eyahlukileyo ukusuka xylem?

Ukuqhuba nezihlunu izityalo: xylem kunye phloem

Zothutho izimbiwa kunye namanzi kwiindawo ezahlukileyo zesityalo eziyimfuneko ilaphu conductive. Le nkqubo ibandakanya iintlobo ezimbini izicwili ezinzima - phloem kunye xylem.

Xylitol obizwa iinkuni kunye phloem - Ngenye indlela. Zidla zibekwe kufutshane nenye kwaye enze imiqadi conductive (ekwabizwa ngokuba ezinezikhondo nemithambo). Xa amalungiselelo macala xylem kunye phloem ayikhuphi iintlobo ezininzi amalaphu conductive:

1. Kollaterialnye (izihlunu ezikufutshane omnye komnye kwaye ibekwe equidistant ukusuka inxalenye yezihlunu yomzimba plant).
2. Bikollaterialnye (xylem engqongwe phloem iinxalenye ezimbini).
3. Concentric (xa xylem ezingqonge phloem and vice versa).
4. Groove (xa phloem kunye xylem of radius lwenzeka striping).

Ubume phloem

plant phloem - uhlobo olulodwa selaphu conductive, nto leyo efunekayo ukuze adlulisele izondlo, kwakheka ngenxa photosynthesis, ukuze amalungu zesityalo, apho zisetyenziswa. Xa uhlobo imvelaphi wohlulwe ezi ndidi zilandelayo:

• ephambili (zahlula of procambium);
• yesibini (ukusekwa cambium).

Umehluko omkhulu wazo kukuba kule phloem zaseprayimari ndingekho ityhubhu amilise okwentliziyo. Nakuba kunjalo, ukwakhiwa kwawo kwifowuni efanayo.

Phloem iqulathe ezi ntlobo iseli zilandelayo:

• yokugalela (ukunika agents transfer zaseprayimari yaye akukho nuclei cell);
• sclerenchyma (ukukhonza ukuxhasa);
• parenchymal (abe sezantsi zothutho ziqu).

Eyona nkalo iiseli yokugalela - ubukho pores ezizodwa ezindongeni. imvelaphi yabo awukacaci. Le namajelo zazizaliswe iziqalelo callose yokugalela (polysaccharide), nto leyo angakhuli kuzo. Callose ukuze occlude imiphantsi iiseli, umzekelo, xa isityalo kwisigaba yokuphumla ebusika.

izithuthi phloem

Phloem - lilaphu, leyo beqhutywa yinto izisombululo oludibeneyo hydrocarbon (ikakhulu sucrose) langena ngenxa photosynthesis. Ukongeza, ezi esigaya kunye metabolites kwiCEMIS, kodwa ephantsi lamanani. Izinga transfer mass ufikelela amashumi eziliqela ngeesentimitha eziyi-ngeyure nganye.

Ukudlulisa izinto ikhutshwa phandle ngamalungu apho kukho izondlo ukusekwa ngenkuthalo, ukuba iinxalenye zezityalo, apho kusetyenziswa okanye lelonani. izinto Active zidluliselwa iingcambu, Namagatya, amagqabi asakhulayo, amalungu okuzala, amatswele, iibhalbhu, rhizomes.

Ngenxa amalinge, abaphengululi bafumanisa ukuba izithuthi ikhutshwa phandle arhente onikele ezo iindawo izityalo zezona zikufuphi kubo. Ukongeza, ukutshintshwa kwezinto ngu abambiseneyo. Ngoko ke, isityalo ngamaxesha ahlukeneyo sexesha lokukhula asinakukwazi ukulandisa izondlo okanye achithe kuzo.

Phloem: umsebenzi

IFotosinthesisi kwenzeka chloroplasts ngamagqabi, kunye inxaxheba kwelanga. iimveliso zayo, amanzi kunye nezinye izisombululo yezimbiwa kwelifunekayo neengcambu izityalo de iyimfuneko ukuze isikolo sisebenze kakuhle zonke iiseli. Phloem - lilaphu ebonelela kwazo zabo. flow nodaka izinto ngentluzo kwiindawo xi ophezulu hydrostatic ukuya kwiindawo ixabiso layo liphantsi. Ngoko ke, lo msebenzi ungundoqo phloem - ukuthuthwa.

Ngokungafaniyo xylem ukusuka phloem

Ngaphandle kwento yokuba xylem kunye phloem enze imisebenzi efana kwaye asondelelene, baye umahluko. Ukufuduka nezinto xylem evela kwi njengengcambu emagqabini. Ngaphezu koko, iiseli okumisele olu hlobo kwilaphu zizinto semithambo, tracheids, imicu neenkuni parenchyma. Xylem kuyimfuneko ukuze idlulise amanzi kunye izondlo iyapheliswa.

Ngoko phloem - yinto uhlobo izihlunu semithambo esityalo. Inceda ukudlulisela nezakhi amalungu zesityalo, apho bakha esebenzayo abekwezo ndawo apho kubekelelwe okanye ziphele. Phloem iquka iintlobo iseli ezintathu - yokugalela, sclerenchyma kunye parenchymal. Iiseli yokugalela umsebenzi zezithuthi zisebenza kunye pores ezikhethekileyo akukho nuclei.

Ukudluliselwa kwezinto enokwenziwa kumacala amabini, kwaye maxa wambi ngesantya ufikelela amashumi eziliqela ngeesentimitha eziyi-ngeyure nganye. Enye Ilaphu conductive, efanayo umsebenzi ukuya phloem, xylem na. Kodwa umahluko zazo eziphambili usendleleni yokuba xylem athuthe kwicala elinye kuphela (ukusuka kweengcambu amahlumelo) emanzini kunye nezithako lichithakale.