Qhov sib txawv tseem ceeb ntawm neural crest thiab neural tube yog qhov neural crest yog ib qho quav ntawm neural phaj qhov twg neural thiab epidermal ectoderms ntsib thaum lub neural raj yog lub embryonic precursor rau hauv nruab nrab lub paj hlwb ntawm vertebrates.
Neural crest thiab neural raj yog ob lub qauv pom nyob rau hauv kev tsim vertebrate embryos. Ob lub qauv yog tsim los ntawm txheej ectoderm. Lub neural crest yog ib pab pawg ntawm cov hlwb ib ntus tam sim no nyob rau hauv dorsalmost cheeb tsam ntawm neural phaj. Cov hlwb ntawm neural crest muaj peev xwm tsiv teb tsaws thiab sib txawv rau hauv ntau hom hlwb. Lub neural raj yog cov qauv tsim los ntawm lub hauv paus paj hlwb tsim. Nyob rau hauv vertebrates, lub neural raj khiav tam sim ntawd saum lub notochord thiab ncua tshaj nws anterior tip.
Neural Crest yog dab tsi?
Lub neural crest yog ob sab sib txuas ib leeg ntawm cov hlwb los ntawm thaj tsam dorsalmost ntawm neural raj. Nws yog tshwj xeeb rau vertebrates. Thiab, nws pib los ntawm ectoderm. Neural crest cells yog cov hlwb uas muaj zog ntau. Cov hlwb no tuaj yeem txav mus rau qhov chaw sib txawv thiab sib txawv rau hauv ntau hom cell. Li no, txoj hmoo ntawm neural crest hlwb nyob ntawm qhov chaw lawv tsiv mus nyob thiab nyob. Neural crest cells migrate thiab sib txawv rau hauv cov hlwb ntawm neural, tawv nqaij, hniav, taub hau, qog adrenal, plab hnyuv, thiab hauv lub embryo. Tsis tas li ntawd, cov hlwb no pab txhawb rau lub paj hlwb peripheral. Yog li ntawd, qhov tseem ceeb ntawm neural crest yog lub peev xwm los mus rau hauv lwm cov ntaub so ntswg embryonic los tsim cov neural thiab non-neural hlwb.
Daim duab 01: Neural Crest Formation
Muaj plaub qhov kev ua haujlwm ntawm lub paj hlwb neural crest. Lawv yog cranial (cephalic) neural crest, pob tw neural crest, vagal thiab sacral neural crest thiab cardiac neural crest.
Neural Tube yog dab tsi?
Neural tube yog lub embryonic precursor rau hauv nruab nrab paj hlwb. Yog li ntawd, tag nrho cov vertebrate embryos muaj ib tug neural raj ua ntej kev loj hlob ntawm CNS. Thaum lub sij hawm thawj neurulation, lub neural raj tsim los ntawm kev loj hlob, invagination ntawm neural phaj hlwb thiab pinching tawm ntawm qhov chaw los ua ib tug hollow raj. Nws thiaj li dhau los ua lub tog raj kheej kaw uas sib cais los ntawm ectoderm nto. Thaum pib, lub neural raj muaj ib txheej. Tom qab ntawd, cov hlab ntsha neural ua multilayered. Nyob rau hauv lub taub hau cheeb tsam, lub neural raj expands tsim lub hlwb. Hauv cheeb tsam pob tw, nws nthuav dav los ua tus txha caj qaum. Yog li, tag nrho lub hauv paus paj hlwb ntawm vertebrates originates los ntawm neural raj.
Daim duab 02: Neural Tube
Thaum lub raj neural tsis kaw kom zoo, neural tube defects tshwm sim. Neural defects yog kev xeeb tub. Spina bifida (tus txha caj qaum tsis xws luag) thiab anencephaly (lub hlwb tsis xws luag) yog ob qho tib si neural tube defects. Lub fetus txha caj qaum tsis kaw tag nrho hauv spina bifida. Feem ntau ntawm lub hlwb thiab pob txha taub hau tsis tsim nyob rau hauv anencephaly. Feem ntau, neural tube defects tshwm sim hauv thawj lub hlis ntawm cev xeeb tub. Li no, lawv raug kuaj xyuas ua ntej tus me nyuam yug los. Neural tube defects tuaj yeem tiv thaiv tau los ntawm kev tau txais folic acid txaus ua ntej thiab thaum cev xeeb tub.
Dab tsi yog qhov zoo sib xws ntawm Neural Crest thiab Neural Tube?
- Neural crest thiab neural tube yog tshwj xeeb rau vertebrates.
- Lawv qhia ectodermal keeb kwm.
- Neural crest originates ntawm cov npoo ntawm neural raj.
- Neural crest cells delaminate los ntawm neural raj thiab tsiv mus nyob ntau.
Qhov txawv ntawm Neural Crest thiab Neural Tube yog dab tsi?
Lub neural crest yog ob sab sib txuas ib leeg ntawm cov hlwb los ntawm thaj tsam dorsalmost ntawm neural raj thaum lub neural raj yog lub embryonic precursor rau hauv nruab nrab paj hlwb ntawm vertebrates. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm neural crest thiab neural raj. Ntxiv mus, lub neural crest tsis pab tsim CNS thaum tag nrho lub hauv paus paj hlwb ntawm vertebrates originates los ntawm neural raj.
Cov duab hauv qab no qhia txog qhov sib txawv ntawm neural crest thiab neural tube.
Summary – Neural Crest vs Neural Tube
Ob leeg neural crest thiab neural raj yog ob lub embryonic qauv ntawm vertebrates. Lub neural crest yog cov pej xeem ntawm ntau lub embryonic hlwb uas tau pinched tawm thaum lub sij hawm tsim ntawm neural raj. Nws cov hlwb delaminate los ntawm cov hlab ntsha neural thiab tsiv mus rau ntau qhov chaw thiab sib txawv rau ntau hom cell. Ntawm qhov tod tes, lub neural raj yog qhov ua ntej rau lub hauv nruab nrab lub paj hlwb ntawm vertebrates. Yog li, qhov no qhia txog qhov sib txawv ntawm neural crest thiab neural tube.
