Phloem - ndi chiyani ichi? Ntchito, dongosolo la phloem, xylem Mosiyana

Phloem - ndi mtundu wapadera wa chomera minofu. Mu chigriki ndi mawu otanthauza "makungwa". Monga mChipangano phloem. Phloem - nsalu imene kulanda zakudya ziwalo mbewu. ndi kapangidwe ka icho chiri? Kodi mayendedwe a zakudya? Kodi osiyana xylem chiyani?

Kuchititsa zimakhala za zomera: xylem ndi phloem

Zoyendera mchere ndi madzi ziwalo zosiyanasiyana za mbewu zofunika nsalu conductive. Amakhala mitundu iwiri ya zimakhala zovuta - phloem ndi xylem.

Xylitol amatchedwanso nkhuni ndi phloem - Lang'anani. Kaŵirikaŵiri inali umakhala pafupi wina ndi mnzake ndi kupanga matabwa conductive (wochedwanso mtima fibrous). Kolongosoka tonse xylem ndi phloem zimatulutsa mitundu yambiri ya nsalu conductive:

1. Kollaterialnye (minofu pafupi wina ndi mnzake ndi ili equidistant ku gawo ofananira wa thupi chomera).
2. Bikollaterialnye (xylem atazunguliridwa ndi zigawo phloem awiri).
3. Concentric (pamene xylem lozungulira phloem ndi mosemphanitsa).
4. Poyambira (pamene phloem ndi xylem wa utali wozungulira amapezeka striping).

Kapangidwe ka phloem ndi

chomera phloem - mtundu wapadera nsalu conductive, imene likufuna popereka zakudya, anapanga chifukwa cha dzuwa, ndi ziwalo chomera, kumene ntchito. Ndi mtundu wa chiyambi lagawidwa mitundu zotsatirazi:

• chachikulu (masiyanidwe a procambium);
• sekondale (linakhazikitsidwa wa cambium).

kusiyana chawo chachikulu ndicho kuti choyambirira phloem kwina chubu mtima woboola pakati. Komabe, zikuchokera awo ma ndi zofanana.

Phloem tichipeza mitundu zotsatirazi selo:

• sieve (kupereka wothandizila kutengerapo pulayimale ndipo alibe mtima khungu);
• sclerenchyma (kutumikira kuthandiza);
• parenchymal (ntchito monga otsika zozungulira zoyendera).

Mbali yaikulu ya maselo sieve - pamaso pa pores wapadera mu maselo makoma a. magwero awo bwinobwino. mitsinje Ng'ona ndi zinthu callose sieve (polysaccharide), amene angathe kudziunjikira mu iwo. Callose mwina occlude njira ya maselo Mwachitsanzo, pamene mbewu mu gawo mpumulo m'nyengo yozizira.

zoyendera phloem

Phloem - nsalu, amene anagwidwa ndi njira kuikapo maganizo a chimasanduka (makamaka sucrose) anapanga chifukwa cha photosynthesis. Komanso, natisunthitsa assimilates ndi metabolites, koma pa woipa m'munsi. misa mtokoma ukufika makumi angapo masentimita paola.

Posamutsa zinthu ikuchitika ndi ziwalo komwe zakudya ndi mwachangu kupangidwa, kuti mbali za zomera, kumene ntchito kapena kuwonjezera. yogwira ndi kunditumiza ku mizu, mphukira, masamba akutulukira, Ziwalo zoberekera, tubers, mababu, rhizomes.

Chifukwa cha zinthu zatsopano, akatswiri anapeza kuti zoyendera imachitidwa ndi mabungwe woperekayo kuti mbali zina za zomera kuti ali pafupi ndi iwo. Komanso, kulanda zinthu ndi amgwirizano. Choncho, mbewu panyengo zosiyanasiyana za nyengo kukula zingaunjikane zakudya kapena amathera iwo.

Phloem: Ntchito

Photosynthesis akupezeka chloroplasts masamba, ndi nawo dzuwa. mankhwala ake, madzi ndi njira zina za mchere chosakanikirana ndi mizu ya zomera ndi kwenikweni zofunikira pa ntchito kwa maselo onse. Phloem - ndi nsalu yomwe imapereka translocation awo. Mtondo otaya zinthu sieve ochokera m'madera a hydrostatic kuthamanga malo kufunika kwake otsika. Choncho, ntchito yaikulu ya phloem ndi - ndi zoyendera.

Mosiyana ndi xylem ku phloem ndi

Ngakhale kuti xylem ndi phloem ntchito zofanana ndipo umakhala pafupi, ali kusiyana. Kupita ku xylem zinthu anachokera ku muzu kuti masamba. Komanso, maselo amapanga mtundu wa nsalu ndi zinthu mtima, tracheids, ulusi ndi nkhuni parenchyma. Xylem M'pofunika kulanda madzi pamodzi ndi zakudya kusungunuka.

Choncho phloem - ndi mtundu wa minofu mtima wa mbewu. Ali kusamutsa chakudya ziwalo chomera, kumene iwo anapanga yolimbikira m'madera kumene iwo ali osungidwa kapena kudyedwa. Phloem tichipeza mitundu selo atatu - sieve, sclerenchyma ndi parenchymal. Waukulu zoyendera ntchito maselo sieve ntchito ndi pores wapadera amene alibe mtima.

Kulanda zinthu angathe kuchitidwa mu mbali ziwiri, ndi liwiro lake zina ukufika makumi angapo masentimita paola. nsalu ina conductive, ofanana mu ntchito kwa phloem ndi, xylem ndi. Koma kusiyana yaikulu kwagona kuti xylem Amakweza njira imodzi yokha (mizu ndi mphukira) madzi ndi mchere kusungunuka.