2024 Tus sau: Elizabeth Oswald | [email protected]. Kawg hloov kho: 2024-01-13 00:07
Ua ntej, txhua tus chromosome ua ib daim qauv ntawm nws tus kheej, khaws nws txuas ntawm ib qho. Lawv condense, tsim ib tug X-puab. Tam sim no cov neeg koom tes chromosome tau ua ke thiab ob, los yog plaub, yuav puag. … Qhov kawg tshwm sim yog phev los yog lub qe qe nrog 23 chromosomes, ib nrab tus lej.
Dab tsi yog qhov teeb meem kawg uas cov phev ntsib ua ntej nws nkag mus thiab fertilize lub qe?
Yuav ua li cas lub qe thawb nrog rau hauv txoj hlab pas? mus fertilize lub qe, phev ntsib obstacles, dab tsi yog qhov kawg lawv ntsib ua ntej lawv nkag mus rau lub qe? noob qhib thiab tawm los ua cov protein. Collagen yog cov protein uas ua rau cov leeg thiab cov pob txha, keratin ua plaub hau.
Cov qauv siv dab tsi los sau cov ntshav thiab cov khoom noj los ntawm cov niam cov ntshav thiab dhau mus rau txoj hlab ntaws?
Cov placenta tso cai rau cov khoom noj thiab cov khoom pov tseg sib pauv ntawm leej niam thiab tus menyuam hauv plab. Tus me nyuam hauv plab txuas nrog lub plab los ntawm txoj hlab ntaws.
Lub blastocyst tawg tawm ntawm Zona li cas?
Zona pellucida yog khaws cia tom qab fertilization thiab nyob ib puag ncig tus neeg tsim embryo rau ob peb hnub. … Kev tawg ntawm zona pellucida tshwm sim nyob rau hauv kev cuam tshuam ntawm ob lub zog: kev siv tshuab siab ntawm cov blastocyst loj hlob ntawm thaj chaw thiab tshuaj lom neeg tawg ntawm cov khoom siv hauv cheeb tsam nrogsecreted lytic enzymes.
DNA zoo heev ua dab tsi?
DNA tau ua yeeb yam rau ntau tshaj plaub txhiab xyoo rau ib qho laj thawj tseem ceeb: nws yog qhov zoo heev zoo ntawm kev luam nws tus kheej. Cov ntawv luam tuaj yeem dhau mus rau tiam tshiab ntawm ob peb txoj hauv kev. Yog tias koj yog kab mob, tej zaum koj yuav tau mus rau hauv cloning-ua cov qauv ntawm koj tus kheej.
Pom zoo:
Lub sijhawm meiosis homologous khub ntawm chromosomes?
Ua ntej cov kab mob nkag mus rau meiosis, lawv feem ntau yog diploid, txhais tau tias lawv muaj ob daim ntawv luam ntawm txhua tus chromosome. Tom qab ntawd, ua ntej cov kab mob nkag mus rau hauv meiosis, nws duplicates nws DNA kom lub cell muaj plaub DNA luam tawm ntawm ob khub ntawm homologous chromosomes.
Yuav ua li cas txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau pom kev pom?
Txawm li cas los xij, corneal collagen cross-linking - cov txheej txheem qib siab tau pom zoo los ntawm US Food and Drug Administration (FDA) hauv xyoo 2016 - tuaj yeem txhim kho qhov pom kev hauv cov neeg mob txhua hnub nyoog. Corneal collagen cross-linking (CXL) tsis yog kho rau keratoconus, tab sis nws tuaj yeem pab tiv thaiv tus mob kom tsis txhob mob hnyav.
Lub sijhawm meiosis thaum twg kev sib tw ntawm chromosomes tshwm sim?
Thaum lub sijhawm prophase I, cov chromosomes condense thiab pom hauv lub nucleus. Vim tias txhua tus chromosome tau muab luam tawm thaum lub sijhawm the S theem uas tau tshwm sim ua ntej prophase I, txhua tus tam sim no muaj ob tus muam chromatids koom nrog ntawm centromere.
Lub sijhawm nyob qhov twg ntawm lub sijhawm teem sijhawm?
kab kab rov tav ntawm lub rooj ntu ntu yog hu ua ntu ntu. Lub sijhawm nyob rau ntawm lub sijhawm nyob qhov twg? Ib lub sijhawm yog kab kab rov tav ntawm lub rooj ntu ntu. Muaj xya lub sij hawm nyob rau hauv lub sij hawm ntawm lub sij hawm, nrog txhua tus pib ntawm sab laug.
Thaum lub sijhawm ntsuas qhov sib npaug ntawm qhov ntsuas cua sov yog nyob rau hauv kev sib cais?
Los ntawm txoj cai thib ob ntawm thermodynamics: Txoj cai thib ob ntawm thermodynamics hais tias qhov entropy ntawm ib qho cais qhov system yeej tsis txo qis, vim tias cov tshuab cais ib txwm hloov mus rau qhov sib npaug ntawm qhov ntsuas kub, lub xeev nrog siab kawg entropy.
