Cov nroj tsuag me (tshwj xeeb yog cov dej) xav tau cov cellulose nyias nyias nyob ib puag ncig cov hlwb kom muaj zog thiab zoo li lub cev. Cov nroj tsuag loj hauv av xav tau kev txhawb nqa ntau dua, sawv cev los ntawm ob hom kev siv tshuab: collenchyma thiab sclerenchyma. Txwv tsis pub, cov ntaub no hu ua kev txhawb nqa lossis txhawb nqa.
Collenchyma yog qhov tsawg dua, tab sis ua lub luag haujlwm tseem ceeb hauv kev tswj hwm cov nroj tsuag ntawm cov nroj tsuag tsim. Lo lus nws tus kheej los ntawm Greek lo lus "kolla" - kua nplaum.
qauv thiab khoom
Txawm hais tias nws muaj nuj nqi txhua yam, collenchyma yog cov nroj tsuag muaj sia muaj peev xwm ntawm photosynthesis. Nws cov protoplasts tsis tuag, thiab cov phab ntsa yog elastic thiab stretch tau.
Lub plasticity ntawm cell membranes yog muab los ntawm ob yam:
- tsis muaj kev sib tw;
- txo qis elasticity ntawm lub plhaub vim yog tso tawm ntawm protoplast (cov ntsiab lus nyob hauv cell).
Collenchyma muajlos ntawm elongated parenchymal los yog prosenchymal hlwb mus txog 2 mm ntev. Lawv lub plhaub yog cov yam ntxwv los ntawm qhov tsis sib xws, uas ua rau cov ntaub so ntswg zoo li peculiar. Qhov tseem ceeb tshaj plaws yog qhov tsis muaj qhov pom ntawm ciam teb ntawm cov phab ntsa thawj thiab theem nrab.
Cov cheeb tsam tuab muaj cov txheej txheem sib hloov, qee qhov muaj cov cellulose feem ntau, thaum lwm tus muaj hemicellulose, pectin thiab dej ntau. Tag nrho cov ntsiab lus ntawm tom kawg yog 60-70% ntawm qhov loj ntawm phab ntsa ntawm tes.
Tsis sib npaug ntawm cov phab ntsa ntawm tes ua rau nws cov yas, thiab tseem tswj cov osmosis (cov ntu nyias tso cai rau dej thiab electrolytes hla). Rau tib lub laj thawj, collenchyma tsis ua nws txoj haujlwm thaum turgor ploj. Ib qho piv txwv yog wilting ntawm nplooj thiab nyom vim dej poob.
Collenchyma yog ib qho derivative ntawm lub ntsiab meristem. Cov hlwb ntawm cov khoom siv kho tshuab no khaws lub peev xwm faib tau ntev.
Toughness rating
Raws li cov neeg kho tshuab lub zog (muaj peev xwm tiv thaiv tearing thiab dabtsi yog khoov), collenchyma tshaj cov yam ntxwv ntawm cam khwb cia txhuas, tab sis yog qhov qis dua rau sclerenchyma. Nyob rau hauv cov laus ntawm cov nroj tsuag, collenchyma hlwb tej zaum yuav dhau mus rau theem nrab thickening thiab lignification, uas ua rau kom cov nqaij mos muaj zog tab sis ua rau nws nkig ntau.
Cov cuab yeej tshwj xeeb - tus nqi siab ntawm cov qauv ntawm elasticity (piv rau txhuas). Qhov no txhais tau hais tias cov ntaub zoo rov qab kho nws cov qauv qub tom qab qhov kev ntxhov siab ntawm cov neeg kho tshuab.
Qhov txawv
Sclerenchyma yog cov ntaub so ntswg "rigid" ntau dua. Nws cov hlwb tsis tsuas yog poob lub peev xwm los faib, tab sis kuj tuag tag vim yog cov phab ntsa tuab lignified uas thaiv kev sib txuas lus nrog ib puag ncig sab nraud.
Sclerenchyma txawv ntawm collenchyma hauv cov hauv qab no:
- tuag ntawm protoplasts;
- uniform thickening ntawm lub plhaub nrog lawv lignification tom ntej;
- cov phab ntsa ntawm tes yog impervious rau dej thiab electrolytes;
- siab zog;
- tsis muaj peev xwm ntawm lub plhaub kom ncab.
Sclerenchyma ua raws li lub cev pob txha nyob rau hauv cov khoom uas twb tsim lawm ntawm cov nroj tsuag. Feem ntau, cov ntaub so ntswg no muaj nyob rau hauv stems nrog rau theem nrab thickening. Sclerenchyma tuaj yeem yog thawj lossis theem nrab, thaum collenchyma tsuas yog thawj.
Lawv ua lawv txoj haujlwm tsuas yog ua ke nrog lwm cov ntaub so ntswg.
Kev ua haujlwm ntawm collenchyma
Nws lub hom phiaj tseem ceeb yog los xyuas kom cov nroj tsuag tsis kam mus rau ntau yam khoom siv (ob leeg zoo li qub thiab dynamic). Tsis tas li ntawd, vim qhov elasticity zoo, cov ntaub no ua kom yooj yim ntawm cov qia thiab nplooj.
Txawm hais tias nws lub zog tsis tshua muaj zog, collenchyma, vim nws cov yas, tsuas yog cov ntaub so ntswg tsim nyog rau cov tub ntxhais hluas kev loj hlob, txij li cov tsos ntawm ib tug nruj sclerenchyma yuav txwv lawv txoj kev loj hlob.
Ntau yam
Raws li qhov xwm txheej ntawm cov phab ntsa ntawm tes, muaj 3 hom kev loj hlob ntawm collenchyma:
- lamellar (zoo rau cov tub ntxhais hluas stems ntawm ntoo ntoo thiab paj noob hlis);
- loose (highlander amphibian, belladonna, coltsfoot).
Nyob zoo ib tsoom niam txiv kwv tij neej tsas sawv daws los koom mloog xov xwm KoomMloogXovXwm TshoojXovXwm
Nyob rau hauv lub ces kaum collenchyma, lub thickening ntawm daim nyias nyias tshwm sim ntawm cov ces kaum ntawm lub hlwb (los ntawm lub npe los). Ntawm kev sib tshuam nrog ib leeg, cov cheeb tsam no sib koom ua ke, tsim cov qauv hauv peb- lossis pentagons (yog tias koj saib ntawm ntu ntawm cov ntaub). Lub thickened seem ntawm daim nyias nyias nyob rau hauv lamellar collenchyma yog teem nyob rau hauv parallel txheej, thiab cov hlwb lawv tus kheej yog elongated raws stems.
Loose collenchyma yog cov ntaub so ntswg nrog tsim cov chaw sib txuas, uas yog tsim los ntawm thaj chaw thickened ntawm daim nyias nyias. Nws yog yam ntxwv ntawm cov nroj tsuag uas tsim cov aerenchyma (cov ntaub so ntswg huab cua) raws li kev hloov mus rau ib puag ncig.
Kev faib tawm hauv lub cev cog
Collenchyma yog cov ntaub so ntswg tshwj xeeb ntawm cov nroj tsuag dicotyledonous, cov tub ntxhais hluas tua, nrog rau cov qauv cog qoob loo uas tsis ua rau cov thickening theem nrab (piv txwv li, nplooj nplooj).
Nws tuaj yeem nyob:
- nyob rau thaj tsam ntawm thawj qia thickening;
- hauv petioles;
- hauv nplooj nplooj ntawm cov nroj tsuag cereal;
- hauv qab daim tawv nqaij;
- tsis tshua muaj hauv cov hauv paus hniav (cab yog ib qho piv txwv).
Nyob rau hauv stems, collenchyma feem ntau yog nyob rau ntawm lub periphery, ze rau ntawm qhov chaw (tej zaum tam sim ntawd nyob rau hauv lub epidermis). Qhov kev faib tawm no muab kev tiv thaiv zoo rau khoov thiab tawg.
Nyob rau hauv cov nplooj ntawm qib microstructural, kev npaj ntawm collenchyma cov ntsiab lus, nrog rau lwm cov ntaub so ntswg txhawb nqa, zoo li tus qauv ntawm I-beam, nyob rau hauv uas ib tug ntsug stands ntawm ob kab rov tav blocks, uas tsis tso cai rau lawv. kom sag nyob rau hauv mechanical action.
