Phloem - dab tsi yog qhov no? Muaj nuj nqi, qauv ntawm phloem, xylem Tsis zoo li

Phloem - yog ib tug tshwj xeeb zoo ntawm tsob nroj cov ntaub so ntswg. Nyob rau hauv lub Greek lus lub sij hawm txhais tau tias "tawv". Raws li nws yog feem ntau hu ua phloem. Phloem - cov ntaub los ntawm kev uas cov kev hloov ntawm cov as-ham rau cov nroj tsuag nrog cev. Yuav ua li cas yog cov qauv ntawm nws yog? Yuav ua li cas yog cov thauj cov as-ham? Yuav ua li cas yog txawv los ntawm lub xylem?

Ua ntaub so ntswg ntawm cov nroj tsuag: xylem thiab phloem

Kev thauj ntawm cov zaub mov thiab dej rau ntau qhov chaw ntawm cov nroj tsuag tsim nyog conductive ntaub. Nws muaj ob hom ntawm complex ntaub so ntswg - phloem thiab xylem.

Xylitol kuj hu ua ntoo thiab phloem - Xijpeem. Lawv feem ntau yog nyob rau hauv zoo sib thooj rau txhua lwm yam thiab tsim tau ib cov conductive beams (kuj hu ua vascular fibrous). Los ntawm kev sib nrig sib kho ntawm xylem thiab phloem emit ob peb hom conductive fabrics:

1. Kollaterialnye (cov ntaub so ntswg uas nyob ib sab mus rau txhua lwm yam thiab nyob equidistant los ntawm cov axial ib feem ntawm cov nroj tsuag lub cev).
2. Bikollaterialnye (xylem surrounded los ntawm phloem ob feem).
3. Concentric (thaum xylem puag ncig lub phloem thiab vice versa).
4. Groove (thaum lub phloem thiab xylem ntawm voos kheej-kheej tshwm sim striping).

Tus qauv ntawm lub phloem

cog phloem - ib tug tshwj xeeb ntawm conductive ntaub, uas yog yuav tsum tau mus kis as-ham, tsim raws li ib tug tshwm sim ntawm photosynthesis, mus rau lub nruab nrog cev ntawm cov nroj tsuag, qhov uas lawv yuav siv tau. Los ntawm hom ntawm keeb kwm yog muab faib mus rau hauv lub nram qab no:

• thawj (differential ntawm procambium);
• theem nrab (tsim ntawm cambium).

Lawv lub ntsiab txawv yog hais tias nyob rau hauv cov thawj phloem tsis tuaj kawm ntawv lub plawv-zoo li tus raj. Txawm li cas los, lawv cov cellular muaj pes tsawg leeg yog zoo tib yam.

Phloem muaj cov nram qab no cell hom:

• sab cib (muab thawj hloov lwm lub tsev neeg thiab tsis muaj cell nuclei);
• sclerenchyma (pab kom txhawb);
• parenchymal (muaj nuj nqi tsawg li tsawg radial thauj).

Lub ntsiab feature ntawm lub suab sib hlwb - lub xub ntiag ntawm tshwj xeeb pores nyob rau hauv lub cell phab ntsa. Lawv cov keeb kwm yog tseem paub tsis meej. Raws yog hlua nrog callose sab cib ntsiab (polysaccharide), uas muaj peev xwm ntxiv nyob rau hauv lawv. Callose yuav occlude raws ntawm lub hlwb, piv txwv li, thaum lub nroj tsuag yog nyob rau hauv ib tug so rau theem nyob hauv lub caij ntuj no.

phloem thauj

Phloem - ib tug ntaub, uas yog tsiv los ntawm concentrated kev daws teeb meem ntawm hydrocarbons (feem ntau sucrose) tsim raws li ib tug tshwm sim ntawm photosynthesis. Nyob rau hauv tas li ntawd, cov kis assimilates thiab metabolites, tab sis nyob rau sab ntau. huab hwm coj mus tus nqi nce mus txog ob peb kaum ntawm centimeters ib teev.

Tshem tshuaj yog nqa tawm los ntawm kabmob uas as-ham yog nquag tsim, mus rau qhov chaw ntawm cov nroj tsuag, qhov uas lawv yuav siv los yog stocking. Active tshuaj yog pauv mus rau cov hauv paus hniav, tua, nplooj tawm, deev kabmob, tubers, qhov muag teev, rhizomes.

Raws li ib tug tshwm sim ntawm thwmsim, tus neeg tshawb fawb pom tias cov thauj yog nqa tawm los ntawm pub lub koom haum rau cov neeg qhov chaw ntawm cov nroj tsuag uas yog ze rau lawv. Nyob rau hauv tas li ntawd, cov kev hloov ntawm tshuaj yog ob sab sib dho. Yog li ntawd, cov nroj tsuag nyob rau hauv sij hawm sib txawv ntawm cov loj hlob rau lub caij yuav noog cov as-ham los yog siv lawv.

Phloem: muaj nuj nqi

Photosynthesis tshwm sim nyob rau hauv lub chloroplasts ntawm nplooj, nrog kev koom tes ntawm tshav ntuj. Nws cov khoom, dej thiab lwm yam kev daws teeb meem ntawm cov zaub mov absorbed los ntawm cov keeb kwm ntawm cov nroj tsuag yog kiag li tsim nyog rau lub hauj lwm ntawm txhua lub hlwb. Phloem - yog ib tug ntaub uas muab lawv cov translocation. Cug ndlwg ntawm sab cib ntsiab los ntawm qhov chaw ntawm siab hydrostatic siab rau qhov chaw ntawm nws uas tsis muaj nqi. Yog li ntawd, lub ntsiab muaj nuj nqi ntawm lub phloem - cov thauj.

Tsis zoo li cov xylem los ntawm cov phloem

Txawm tias muaj tseeb hais tias cov xylem thiab phloem ua zoo xws li cov functions thiab yog nyob ze sib thooj, lawv muaj sib txawv. Tsiv nyob rau hauv xylem tshuaj muab los ntawm hauv paus mus rau lub nplooj. Ntxiv mus, lub hlwb constituting no hom ntawm ntaub yog vascular hais, tracheids, fibers thiab ntoo parenchyma. Xylem yog tsim nyog rau cov kev hloov ntawm cov dej nrog rau cov yaj cov as-ham.

Yog li ntawd phloem - yog ib hom ntawm vascular cov ntaub so ntswg ntawm cov nroj tsuag. Nws ua hauj lwm pab mus rau cov hloov cov as-ham los ntawm cov kabmob ntawm cov nroj tsuag, qhov uas lawv tsim ib tug active nyob rau hauv cov qhov chaw uas lawv muaj tseg los yog noj. Phloem muaj peb cell hom - sieve, sclerenchyma thiab parenchymal. Lub ntsiab thauj nuj nqi sab cib hlwb ua hauj lwm nrog tshwj xeeb pores uas muaj tsis muaj nuclei.

Hloov ntawm tshuaj yuav tsum nqa tawm nyob rau hauv ob cov lus qhia, thiab nws ceev tej zaum nce mus txog ob peb kaum ntawm centimeters ib teev. Lwm conductive ntaub, zoo ib yam li nyob rau hauv nuj nqi rau phloem, xylem yog. Tab sis lawv lub ntsiab txawv nyob rau hauv lub fact tias xylem thauj tsuas yog ib qho kev taw qhia (los ntawm cov hauv paus hniav rau tua) dej nrog yaj minerals.