dead phloem, is known as rhytidome. Cov kab mob cork tuag yog kab nrog suberin, cov khoom muaj roj uas ua rau lawv tsis muaj dej ntau rau cov pa roj thiab dej. Kev sib pauv roj nruab nrab ntawm cov ntaub so ntswg ntawm cov tawv ntoo thiab cov stems thiab lawv qhov chaw nyob ib puag ncig yuav tshwm sim los ntawm qhov chaw spongy (lenticels) hauv cork.
rhytidome yog dab tsi?
Lub rhytidome yog qhov paub zoo tshaj plaws ntawm cov tawv ntoo, yog txheej txheej txheej uas npog cov pob tw ntawm cov ntoo. Nws yog tsim los ntawm feem ntau ntawm cov hlwb tuagthiab yog tsim los ntawm ntau txheej txheej ntawm suberized periderm, cortical thiab phloem cov ntaub so ntswg. Lub rhytidome yog tshwj xeeb tshaj yog zoo tsim nyob rau hauv cov laus stems thiab cov cag ntoo.
Lub luag haujlwm ntawm rhytidome yog dab tsi?
Cov tawv tawv sab nrauv, muaj feem ntau ntawm rhytidome, yog txheej tiv thaiv uas txwv kev nkag ntawm cov kab thiab kab mob thiab tseem tiv thaiv cov ntaub so ntswg sab hauv los ntawm qhov kub thiab txias.
Vim li cas sab tawv thiaj tuag?
Cov tawv tawv mos, los yog bast, yog tsim los ntawm vascular cambium; nws muaj cov ntaub so ntswg phloem theem nrab uas nws cov txheej sab hauv tshaj conveys zaub mov los ntawm nplooj mus rau tag nrho cov nroj tsuag. … Cov tawv tawv sab nrauv, uas feem ntau yog cov ntaub so ntswg tuag, yog khoom ntawm cork cambium (phellogen).
Ib tug phloem theem nrab tuag los yog ciaj sia?
Phloem Secondary tswj living parenchyma hlwb rau ntau xyoo tom qab cov khoom siv hluav taws xob tau tso tsegmuaj nuj nqi, zoo li theem nrab xylem. Kev nthuav dav callose deposition (qee zaum hu ua callose) nyob rau hauv sieve ntsiab lus cim qhov kawg ntawm lawv lub neej ua haujlwm.
