Qhov sib txawv tseem ceeb ntawm protoxylem thiab metaxylem yog tias protoxylem yog thawj tsim thawj xylem uas muaj cov hlwb me, tshwj xeeb tshaj yog cov hlab ntsha nqaim thiab tracheids thaum metaxylem yog tom qab tsim thawj xylem uas muaj cov hlwb loj, tshwj xeeb tshaj yog cov hlab ntsha, thiab cov hlab ntsha..
Xylem yog ib qho ntawm ob hom kab mob vascular hauv cov nroj tsuag. Xylem ua rau nce siab ntawm cov dej thiab cov zaub mov los ntawm cov hauv paus hniav mus rau lwm qhov ntawm cov nroj tsuag. Nws yog cov qauv zoo li lub raj uas muaj ntau hom tshwj xeeb ntawm cov hlwb xws li cov hlab ntsha, tracheids, parenchyma, thiab fibers. Muaj ob hom xylems ua thawj xylem thiab thib ob xylem. Thawj xylem loj hlob thaum lub sij hawm thawj kev loj hlob. Tsis tas li ntawd, thawj xylem muaj ob ntu: protoxylem thiab metaxylem. Ob leeg protoxylem thiab metaxylem yog los ntawm cov pro-cambium thaum lub sij hawm thawj kev loj hlob. Protoxylem originates ua ntej, thiab metaxylem originates tom qab protoxylem.
YProtoxylem yog dab tsi?
Protoxylem yog thawj xylem uas tsim thawj zaug thaum thawj kev loj hlob. Protoxylem matures ua ntej cog cov kab mob ua kom tiav lawv elongation. Nyob rau hauv ib lub qia, protoxylem nyob rau sab nraud. Nws muaj cov cell me. Hauv lwm lo lus, nws muaj cov hlab ntsha nqaim thiab tracheids. Li no, lub lumen ntawm lub hlwb yog nqaim.
Daim duab 01: Protoxylem
Tsis tas li ntawd, lignification tsis dav hauv cov cell protoxylem. Cov hlab ntsha Protoxylem qhia txog qhov sib npaug thiab muab kauv tuab hauv lawv cov phab ntsa hauv nruab nrab. Tsis tas li ntawd, protoxylem muaj ntau ntawm parenchyma, thiab nws tsis muaj xylem fibers. Piv nrog rau metaxylem, protoxylem tsis tshua muaj txiaj ntsig hauv dej conduction.
Metaxylem yog dab tsi?
Metaxylem yog ib feem ntawm thawj xylem uas tsim tom qab protoxylem. Metaxylem matures tom qab ua tiav ntawm kev loj hlob ntawm cov nroj tsuag hauv nruab nrog cev. Nws yog nyob rau sab hauv ntawm qia. Metaxylem muaj cov hlwb loj dua li cov hlab ntsha dav thiab cov tracheids. Li no, lub lumen ntawm cov hlwb loj dua piv rau cov lumen ntawm cov protoxylem hlwb.
Daim duab 02: Metaxylem
Tsis tas li ntawd, cov hlwb metaxylem muaj qhov ua kom pom tseeb. Metaxylem hlab ntsha qhia scalariform, reticulate thiab pitted thickenings nyob rau hauv lawv ob lub cell phab ntsa. Tsis tas li ntawd, metaxylem muaj xylem fibers thiab tsawg ntawm parenchyma hlwb. Metaxylem muaj txiaj ntsig zoo hauv kev ua dej thiab cov zaub mov ntau dua li protoxylem.
Qhov Zoo sib xws ntawm Protoxylem thiab Metaxylem yog dab tsi?
- Protoxylem thiab metaxylem yog ob hom thawj xylem uas ua dej thiab minerals.
- Lawv tshwm sim hauv cov nroj tsuag vascular.
- Tsis tas li, ob qho tib si raug tsim thaum lub sijhawm loj hlob ntawm cov nroj tsuag.
- Ntxiv mus, ob qho tib si los ntawm procambium.
- Tsis tas li ntawd, ob qho tib si protoxylem thiab metaxylem muaj cov nyob thiab cov hlwb tuag.
Qhov txawv ntawm Protoxylem thiab Metaxylem yog dab tsi?
Y Primary xylem muaj ob ntu ua protoxylem thiab metaxylem. Ob qho tib si tsim thaum lub sij hawm loj hlob. Txawm li cas los xij, protoxylem yog thawj qhov tsim ntawm thawj xylem thaum metaxylem yog tom qab tsim ib feem ntawm thawj xylem. Yog li, peb tuaj yeem xav txog qhov no yog qhov sib txawv tseem ceeb ntawm protoxylem thiab metaxylem. Feem ntau, protoxylem muaj cov hlwb me; li no nws tsis tshua muaj meej. Whereas, metaxylem muaj cov hlwb loj dua thiab tseem ceeb dua. Yog li, qhov no kuj yog qhov txawv ntawm protoxylem thiab metaxylem.
Ntxiv mus, qhov sib txawv ntxiv ntawm protoxylem thiab metaxylem yog tias cov protoxylem muaj ntau dua parenchyma hlwb thiab tsis muaj xylem fibers, tab sis metaxylem muaj xylem fibers thiab muaj ob peb parenchyma hlwb. Ib qho sib txawv ntxiv ntawm protoxylem thiab metaxylem yog qhov ua tau zoo ntawm kev ua dej. Protoxylem tsis tshua muaj txiaj ntsig thaum metaxylem muaj txiaj ntsig ntau dua hauv kev ua dej. Tsis tas li ntawd, cov lignification tsis dav hauv cov cell protoxylem thaum lub lignification yog dav hauv metaxylem cells.
Cov hauv qab no nthuav tawm cov ntsiab lus ntxiv ntawm qhov sib txawv ntawm protoxylem thiab metaxylem.
Summary – Protoxylem vs Metaxylem
Protoxylem thiab metaxylem yog ob hom thawj xylems tsim thaum lub sij hawm loj hlob ntawm cov nroj tsuag vascular. Protoxylem yog thawj tsim thawj xylem uas matures ua ntej cov nroj tsuag kab mob ua kom tiav lawv elongation thaum metaxylem yog tom qab tsim thawj xylem uas matures tom qab ua tiav ntawm kev loj hlob ntawm cov nroj tsuag kab mob. Ntxiv mus, protoxylem muaj cov cell me. Whereas, metaxylem muaj cov cell loj dua. Tsis tas li ntawd, lignification tsis dav hauv protoxylem; Yog li ntawd, nws yog tsawg npaum li cas nyob rau hauv dej conduction. Metaxylem qhia tau hais tias ntau dua lignification; yog li nws muaj txiaj ntsig zoo hauv kev siv dej. Yog li, qhov no qhia txog qhov sib txawv ntawm protoxylem thiab metaxylem.
