Qhov Tseem Ceeb Qhov txawv - Holoblastic vs Meroblastic Cleavage
Holoblastic cleavage raug xa mus rau tag nrho embryonic cell cleavage thaum meroblastic cleavage raug xa mus rau ib nrab embryonic cell cleavage. Qhov no yog qhov sib txawv tseem ceeb ntawm Holoblastic thiab Meroblastic Cleavage.
Cleavage txhais tau tias yog kev faib cov hlwb thaum lub sijhawm embryonic thaum ntxov. Qhov no tshwm sim thaum cov kauj ruam fertilization tiav thiab lub zygote yog tsim. Cleavage yog pib nrog kev ua haujlwm ntawm cyclin tus neeg raug foob kinase. Ob hom cleavages muaj nyob ntawm seb cov yolk muaj nyob rau hauv lub qe. Lawv yog holoblastic cleavage los yog meroblastic cleavage.
Holoblastic Cleavage yog dab tsi?
Holoblastic cleavage txhais tau tias yog ib hom kev sib cais uas tshwm sim hauv cov embryonic hlwb uas tsis muaj cov qe loj loj (nruab nrab rau cov qe qe). Hom cleavage no tshwm sim nyob rau hauv isolecithal hlwb. Isolecithal hais txog txawm tias kev faib tawm ntawm cov yolk nyob rau hauv cytoplasm ntawm mammalian ovum.
Holoblastic cleavage tuaj yeem yog plaub hom cleavage loj; Ob sab holoblastic, radial holoblastic, rotational holoblastic thiab kauv holoblastic. Ob sab holoblastic cleavage yog hais tias yog thawj hom cleavage uas bisects lub zygote rau hauv ob halves; sab laug thiab sab xis. Radial cleavage yog tus cwj pwm los ntawm kev teeb tsa ntawm blastomeres ntawm txhua qib siab ncaj qha rau ntawm cov qib qis tom ntej uas ua rau radial symmetry nyob ib ncig ntawm tus ncej rau ncej axis ntawm lub embryo.
Daim duab 01: Holoblastic Cleavage
Thaum lub sij hawm tig holoblastic cleavage, qhov qub thawj faib uas tshwm sim raws li meridional axis thiab ces tig nyob rau hauv 90 degrees thiab muab rau lwm lub hlwb. Kauv holoblastic cleavage tshwm sim nyob rau hauv ib ncig ntawm tus ncej rau ncej axis ntawm lub embryo.
Meroblastic Cleavage yog dab tsi?
Meroblastic cleavage txhais tau tias yog hom cleavage uas tshwm sim nyob rau hauv lub qe fertilized nrog ib tug loj npaum li cas ntawm yolk thiab undergoes ib nrab cleavage. Meroblastic cleavage tuaj yeem muab faib ua ob ntu; disoidal cleavage thiab superficial cleavage.
Thaum lub sijhawm sib cais, qhov cleavage furrow uas tsim los tsis nkag mus rau lub qe. Hom cleavage no feem ntau pom muaj nyob rau hauv hom xws li monotremes, avians, tsiaj reptiles thiab ntses uas muaj qe telolecithal.
Daim duab 02: Meroblastic Cleavage
Thaum lub sijhawm cleavage superficial, cov txheej txheem ntawm mitosis tshwm sim yam tsis muaj cytokinesis. Superficial cleavage ua rau lub cell polynuclear. Ntawm no, lub yolk yog positioned nyob rau hauv nruab nrab ntawm lub qe cell qhov twg lub nuclei tau tsiv mus nyob rau periphery ntawm lub qe.
Dab tsi yog qhov zoo sib xws ntawm Holoblastic thiab Meroblastic Cleavage?
- Ob leeg Holoblastic thiab Meroblastic Cleavage yog ob hom cleavages.
- Ob leeg tshwm sim thaum lub sijhawm embryonic.
- Ob leeg yog tshwm sim los ntawm cyclin-dependent kinase complex.
- Ob qhov cleavages xaus nrog kev tsim ntawm blastula.
Qhov txawv ntawm Holoblastic thiab Meroblastic Cleavage yog dab tsi?
Holoblastic vs Meroblastic Cleavage |
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| Holoblastic cleavage txhais tau tias yog ib hom cleavage uas tshwm sim nyob rau hauv lub embryonic hlwb uas muaj ib tug nruab nrab los yog sparse ntawm yolk nyob rau hauv lub zes qe menyuam. | Meroblastic cleavage txhais tau tias yog hom cleavage uas tshwm sim nyob rau hauv lub qe fertilized nrog ib tug loj npaum li cas ntawm yolk thiab undergoes ib nrab cleavage. |
| Mitosis | |
| Tsis muaj mitosis tshwm sim hauv holoblastic cleavage. | Mitosis tshwm sim hauv meroblastic cleavage. |
| Ntau Yolk hauv Qe | |
| me me ntawm cov qe muaj nyob rau hauv cov qe uas qhia tias holoblastic cleavage. | Ntau dua ntawm cov qe muaj nyob rau hauv cov qe uas qhia meroblastic cleavage. |
| Hom Cleavage | |
| Holoblastic cleavage ua rau kom tiav cleavage. | Meroblastic cleavage ua rau ib nrab cleavage. |
| subtypes | |
| Ob sab holoblastic, radial holoblastic, rotational holoblastic thiab kauv holoblastic yog hom holoblastic cleavage. | Discoidal cleavage thiab superficial cleavage yog hom meroblastic cleavage. |
| Synonyms | |
| Holoblastic cleavage - Tag nrho cleavage thiab tiav cleavage yog synonyms ntawm holoblastic cleavage. | Tsis tiav cleavage lossis ib nrab cleavages yog cov lus piv txwv rau meroblastic cleavage. |
| Examples | |
| Feem ntau ntawm cov deuterostomes thiab protostomes xws li amphibians, tsiaj nyeg, echinoderms, annelids, flatworms, nematodes, thiab lwm yam qhia holoblastic cleavage. | Monotremes, avians, tsiaj reptiles qhia meroblastic cleavage. |
Summary – Holoblastic vs Meroblastic Cleavage
Cleavage txhais tau tias yog kev faib cov hlwb uas tshwm sim thaum ntxov embryology. Nws yog ob hom; holoblastic cleavage thiab meroblastic cleavage. Qhov no nyob ntawm tus nqi ntawm yolk tam sim no nyob rau hauv lub qe. Holoblastic cleavage ua rau ua tiav cleavage thaum meroblastic cleavage ua rau ib nrab cleavage. Qhov kawg tshwm sim ntawm ob qho tib si cleavages yog blastula. Qhov no yog qhov txawv ntawm holoblastic cleavage thiab meroblastic cleavage.
