Ngaphakathi kwezityalo ze-vascular, oko kukuthi, ii-angiosperms, ii-gymnosperms kunye ne-pteridophytes (ferns), kukho imijelo apho ukuthuthwa kuthunyelwa khona. Aba babiziwe xylem kunye ne-phloem.
Kungaphantse kuthiwe bafana nemithambo yezilwanyana, phakathi kwazo esizibandakanya kuzo, kuba zizalisekisa umsebenzi ofanayo. Kodwa yintoni kanye kanye?
Yintoni i-xylem kunye ne-phloem kwaye yintoni umsebenzi wabo?
Umfanekiso - iTypede.eu
Ukuqonda ukubaluleka kwazo, kufuneka uqale ubazi ukuba ziyintoni na kwaye ziyintoni na iimpawu zazo. Ke masize kuyo:
Xylem
El xylem Sisipha esine-lignified (yiyo loo nto saziwa ngokuba ngumthi) esenziwe ziindidi ezahlukeneyo zeeseli ezimile kwimibhobho encinci. Ezi zinodonga lweseli lwesibini olubanika ukuxhathisa. Zimbini iintlobo ze-xylem ezahlukileyo:
- Iiprayimari: iqulathe iprotoxylem kunye nemetaxylem.
- Iprotoxylem: sisihlunu sokuqala esibonakaliswe ngokuba neenqanawa ezirinjiweyo okanye ezijikelezayo, ukongeza ekuqiniseni umbulelo apho zinokuziqhelanisa nokukhula kwezityalo.
- I-Metaxylem: Yenziwa ziinqanawa ezibhalwe kwakhona kunye ne-scalariform, kwaye zinobubanzi obukhulu kunaleyo yeprotoxylem. Zizityalo ezincinane kuphela ezinazo. Njengoko bekhula, i-metaxylem ikhula.
- Isekondari: yiyo evelisa icambium *. Ezi zinto zahlukile:
- Abaqhubi: zenziwe ngeenqanawa ezidityanisiweyo ezithi zigqitywe ezindongeni zazo, kunye neetracheids ezinemibhobho ephezulu.
- Ukungahambisi kakuhle: ziintsinga ze-xylem.
*I-Cambium ifumaneka kuphela kwizityalo ezinobunzimanjengemithi. Amacandelo amabini eeseli zabantu abadala ayahlukaniswa: eyokuqala, ebekwe nzulu ngaphakathi esiqwini, yiyo eyenza iinkuni, kwaye apho amakhonkco okukhula akhiwa khona; okwesibini, kwelinye icala, kunxulunyaniswa ne-phloem kwaye kulapho kuthuthwa khona incindi ecacisiweyo.
Yintoni umsebenzi weXylem?
Ukhathalela ukuhambisa amanzi kunye neetyiwa zetyuwa ukusuka ezingcanjini ukuya emagqabini. Lo mxube 'wezithako' ubizwa ngokuba yincindi eluhlaza. Ngenxa yeempawu zayo, ikwanika uzinzo kwisityalo.
Kuyimfuneko ukongeza ukuba xa isityalo sikhule ngokupheleleyo, i-xylem sisicubu esiphilayo, kodwa xa ikhula, iba sisicwili esifileyo.
Phloem
Izityalo zenza into ekungekho namnye kuthi onokuyenza: yenza ifotosinthesis, okanye yintoni eza kwinto enye: ukuvelisa ukutya kwayo ngenxa yelanga kunye nekhabhon diokside. Kodwa ukuze oku kutya kufikelele kuwo onke amalungu alo, kuyimfuneko ukuba ineenqanawa ezihambisayo, ezaziwa ngegama le-phloem, okanye iiglasi zaseLiberia.
Sifumana i-phloem kuso sonke isityalo, ukuze sikwazi ukufumana ukuba kubaluleke kangakanani kuso. Yenziwe ziindidi ezimbini ezahlukeneyo zeeseli:
- Iityhubhu zesisefo: zinobume obude, kwaye zicwangciswe ngokuthe nkqo. Iiseli zahlulwe zodwa, kwaye zinezinto zokugqobhoza apho izinto ezithile zidlula.
- Iiseli eziqhotyoshelweyo: zincinci ngobukhulu, kwaye ukumila kwazo akuqhelekanga. Umsebenzi wawo kukulawula umsebenzi weeseli zesisefe.
Yintoni umsebenzi wephloem?
Phloem inoxanduva lokuhambisa izakhamzimba ukusuka emagqabini ukuya kwezinye izityalo. Ezi ziyaziwa ngokuba yincindi yokucola. Yinyama ephilayo ke, kwaye ihlala injalo ide ifikelele esiphelweni sobomi bayo.
Nguwuphi umahluko phakathi kwe-xylem kunye ne-phloem?
Icandelo lomnqamlezo lesiqu seflakisi. 1. medulla, 2. protoxylem, 3. xylem, 4. phloem, 5. sclerenchyma, 6. cortex kunye 7. epidermal tissue.
Ngaphandle kweempawu zayo ezisisiseko, umahluko ophambili phakathi komnye nomnye kukuba i-xylem inoxanduva lokuhambisa incindi eluhlaza ukusuka ezingcanjini isiya emagqabini, kwaye incindi ye-phloem iveliswe kwicala elahlukileyo.. Yintoni enye kunye nenye incindi eyenziwe ngayo?
- Incindi eluhlaza: olu hlobo luqulathe uninzi ngamanzi, kodwa kunye neeminerali kunye nokukhula rhoqo, kunye nezinye izinto ezichithakeleyo.
- Inkqubo esetyenzisiweyo: inamanzi, izimbiwa, iswekile kunye neepytoregulators.
Njengoko ubona, i-xylem kunye ne-phloem ngamacandelo amabini ahlukeneyo kakhulu ezityalo, kodwa zinemisebenzi ebalulekileyo.