Xylem yog cov ntaub so ntswg uas muaj cov hlwb tuag, hollowed-out hlwb uas tsim cov kav dej. Cov phab ntsa ntawm xylem cells yog lignified (muaj zog nrog cov khoom hu ua lignin). Qhov no tso cai rau lub xylem tiv thaiv kev hloov pauv thaum dej txav los ntawm cov nroj tsuag.
Pob xylem hlwb puas muaj kauv ntawm lignin?
Lub phab ntsa xylem yuav tsum muaj qhov khoob (qhov), uas ua kom muaj kev sib pauv ntawm cov dej molecules. Lignin tuaj yeem sawv cev los ntawm ib qho spiral (coiled) lossis annular (rings) kev npaj.
Leej twg hauv qab no muaj lignin?
lignin yog tso rau hauv tracheids, hlab ntsha, fiber ntau ntawm xylem thiab phloem thiab sclerenchyma.
Cov ntaub so ntswg twg muaj kauv Thickenings ntawm lignin?
Xylem hlwb muaj cov qauv tshwj xeeb ntawm cov phab ntsa ntawm phab ntsa, xws li kauv lossis pitted qauv.
Ploem hlwb puas muaj lignin?
Phloem yog cov raj hollow ua los ntawm ntau lub hlwb txuas (sieve hlab ntsiab). Cov phab ntsa ntawm tes ntawm txhua lub hlwb raug perforated rau hauv cov qauv hu ua sieve daim hlau. … Cov hlwb tuag thiab hollow thiab muaj cov phab ntsa tuab tuab heev uas yog impregnated nrog lignin
