Amfrayo ci gaban zamani

Lokacin tayi, anan ake magana a kai a matsayin embryogenesis, fãra daga wani fili daga cikin nuclei na mace da namiji gametes da kuma wakiltar da hadi tsari. Saboda haka, ga wadanda kwayoyin cewa ayan pre-Natal ci gaba, embryogenesis ƙare da haihuwa, a cikin kwayoyin da irin larval ci gaba - da barin tayi membranes.

Amfrayo ci gaban zamani yana da dama, saukarwa:

1.Zigota. A hadi namiji jima'i cell, kai da kwai, ya sa ta ci gaba. Yana fara zuwa faruwa sinadaran da jiki matakai da taimakawa ga samuwar fasali na kwai, da kawar membranes nuclei, sakamakon biyu cell nuclei fis, kuma an kafa na DNA.

2. Hudamah (na farko mataki na ci gaba da zygote) - ya zama rabo na zygote. A kwai, wanda aka motsi saukar da fallopian tube, GROOVES aka kafa, inda a can ne cell division. Kafa a wannan hanya Kwayoyin kira morula. Wannan mataki da aka gwada duk kwayar kwayoyin cewa haifa jima'i daban-daban ne kawai kan aiwatar da cell division (radial, cinikin da ke tsakanin, karkace).

A siffa daga cell division ne cewa ba su girma. Wannan tsari ya shafi samuwar daya manyan Kwayoyin (kwai cell) manyan yawan kananan Kwayoyin tare da m cytoplasm kusa da nuclei.

Amfrayo lokaci ba ya kawo karshen nan, la'akari da wadannan ci gaban da tayi mataki.

3. A blastula (samuwar kwayar Tsarin cikin wani nau'i na kumfa) - kunshi wani Layer na sel cewa an kira a matsayin tayi. blastula size halarci girman da kwai, don haka a lokacin cell division, da yawan nuclei da DNA ƙaruwa.

4. Gastrulation - mataki motsi tayi Kwayoyin, sakamakon samuwar uku Layer tayi takardar. Wannan mataki ne halin da karuwa a cikin kira na sunadaran da ribosomes, a cikin wannan lokaci akwai protrusion na iyakacin duniya (vegetative) blastula baxini, daura da sandunan suna da alaka, da kuma wani rami da aka shafe blastula. Wannan halitta wani sabon kogo, da ake kira blastopore ko primary bakinka.

Saboda haka, a dole karfin juyi gastrulation tayi ci gaba, tun amfrayo lokaci a wannan mataki damar da samuwar ta gabobin da kyallen takarda da kuma sashin jiki tsarin.

Ya kamata a lura, da samuwar tsokoki da kuma gabobin da tayi a daban-daban lokaci da daban-daban ji na ƙwarai to tareda žata muhalli tsoma, kamar cututtuka, radiation ko sunadarai jamiái. Wadannan lokaci na ƙara ji na ƙwarai ake kira m, a can ne ya karu alama na tasowa munanan.

Alal misali, da amfrayo lokaci ne 'yan m maki. Bari mu auna su a mafi daki-daki:

1. blastula lokaci (na farko da makonni biyu bayan ganewa) - tayi ko dai ya mutu, ko ya ci gaba da halittu farfadowa ba tare da sabawa. A wannan lokaci a manyan yawan mutu tãyuna (40%), wanda ya fara da ci gaban mutated jam sel.

2. A ashirin ga sabain rana bayan hadi - da tsawon mafi girma shigewa amfrayo kamar fara da za a dage farawa da ta samar da duk muhimmanci gabobin.

3. Zamanin tayi ne halin da m girma da tayin. Ga quite sau da yawa a can iya zama wani take hakkin da cin kawai a cikin wadanda gabobin, wanda ba a kammala su samuwar.

Saboda haka, tayi ontogenesis lokaci halin da samuwar kuma ci gaban da tayi ta cell division, samuwar da kyallen takarda, gabobin da kuma tsarin. Daban-daban kwayoyin bambanta da wannan lokaci, amma a cikin wani hali, shi zai fara a ganewa da kuma ƙare da haihuwar wata sabuwar rayuwa.