2024 Tus sau: Elizabeth Oswald | [email protected]. Kawg hloov kho: 2024-01-13 00:07
Tom qab ovulation lub oocyte raug ntes nyob rau hauv metaphase ntawm meiosis II mus txog fertilization. Thaum fertilization, tus thib ob oocyte ua tiav meiosis II los ua ib tug laus oocyte (23, 1N) thiab ib tug thib ob polar lub cev.
Thaum twg thiab qhov twg oocyte ua tiav meiosis 2 yuav tshwm sim li cas thaum nws ua tiav meiosis 2?
Kev ua tiav ntawm Meiosis ntawm fertilization
-Yog tias fertilization tshwm sim, qhov thib ob oocyte yuav ua tiav meiosis II mus rau ua ib lub qe loj (tag nrho mature) thiab lub polar thib ob lub cev uas tau degenerated. SRY protein yuav txhawb txoj kev loj hlob ntawm qog nqaij hlav.
Dab tsi ua rau meiosis II hauv oocyte?
Tham qhov kev ntes yog vim tsis muaj cov kab mob ntawm tes txaus kom tso cai rau kev loj hlob meiotic. Txawm li cas los xij, raws li oocyte loj hlob, cov proteins no tau tsim, thiab meiotic raug ntes tau nyob ntawm cyclic AMP. … Kev tshem tawm ntawm oocyte los ntawm cov hauv paus hniav ua rau meiosis mus rau hauv oocyte.
Pob oocyte theem nrab ua tiav?
Hauv tib neeg, cov oocytes thib ob yog tsim thaum thawj oocytes ua tiav meiosis I. … Yog li, thaum cov phev cell fertilizes poj niam txiv neej cell lub oocyte thib ob oocyte sai sai ua tiav cov seem ntawm meiosis II, ua rau ib tug ootid thiab ovum, uas cov phev cell koom nrog.
Dab tsi ua rau oocyte theem nrab ua kom tiav meiosis II?
Tus thib ob oocyte ua tiav meiosis IItsuas yog thaum fertilized los ntawm spermatozoan. Tom qab pib fertilization, lub thib ob oocyte pib nws thib ob meiotic division, uas ua rau tsim ib tug paub tab ovum thiab lwm lub cev polar. Lub sijhawm no, lub zes qe menyuam tau npaj fuse nrog cov spermatozoan.
Pom zoo:
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.
Qhov twg yog qhov tsis tiav lossis tsis tiav?
Tus raug tus lej tsis tiav. Cov lus qhia "tsis tiav" tsis muaj nyob. Yog hais tias koj xav qhia tias ib tug neeg coj ib yam dab tsi uas tau ua tiav thiab ua tsis tiav, koj yuav tsum tau hais tias: Nws tshem lub cog log ntawm lub cav, rendering nws tsis tiav.
Thaum twg oocytes tsim hauv tib neeg poj niam?
Tag nrho cov thawj oocytes yog tsim los ntawm lub hlis thib tsib ntawm lub neej hauv plab thiab nyob twj ywm nyob rau hauv prophase ntawm meiosis kuv mus txog rau thaum laus laus. Thaum lub sij hawm ib tug poj niam lub zes qe menyuam voj voog ib oocyte raug xaiv los ua kom tiav meiosis kuv los ua ib tug thib ob oocyte (1N, 2C) thiab thawj lub cev polar.
Nyob rau hauv pteridophytes meiosis tshwm sim thaum twg?
Meiosis tshwm sim hauv sporangia, nyob rau hauv qab ntawm nplooj sporophyte. Tom qab cov spores raug tso tawm lawv germinate, faib los ntawm mitosis thiab loj hlob mus rau hauv lub plawv zoo li gametophytes. … Lub embryo loj hlob mus rau sporophyte, tseem txuas nrog gametophyte.
Thaum twg kuv tuaj yeem muab cov ntaub pua plag rau hauv cov plag tsev ua kom tiav?
Tau 3 lub lis piam ua ntej muab cov ntaub pua tsev rau ntawm cov ntaub pua tsev tshiab tshiab / ua tiav. Tos 48 mus rau 72 teev tom qab cov ntoo tawv tau ua kom tiav / tiav ua ntej "PLACING" rooj tog rov qab rau hauv nws qhov chaw.
