BIOM 3040 Study Guide - Final Guide: Decidua, Glycogen, Apposition
Document Summary
Cleavage occurs about 24 hours after fertilization. Rapid cell divisions converts unicellular zygote into multicellular embryo. Non-synchronos see embryos with odd number of cells. No growth remains about 0. 1mm in diameter. Blastomeres up until 8 cell stage are totipotent important in twinning! 16 cell stage form a morula. At the blastocyst stage mitosis converts back to the regular cell cycle (growth stages) Outer blastomeres adhere to eachother to form the 16 cell morula. Embryo is more compact, cells lose individual identity. Can act independently as adhesion molecules or as part of junctions (gap and tight functions) Many types: e (epithelial), n (neurons), p (placenta) Tra(cid:374)s(cid:373)e(cid:373)(cid:271)ra(cid:374)e seri(cid:374)e protease that"s fou(cid:374)d to (cid:271)e asso(cid:272)iated with e-cadherins in many tissues. At the 8 cell stage epithin and e-cadherins colocalize. Outer blastomeres secrete fluid into the middle forms the blastoceole and divides cells into the outer cell mass (trophoblast) and inner cell mass.