BIOL 3P28 Study Guide - Midterm Guide: Spliceosome, Histone H2B, N-Terminus
6 Dec 2013
School
Department
Course
Professor
Document Summary
Fusion of gamete nuclei (1/2 of normal chromosomes) gives a complete genome. Exocytosis releases onto oocyte to digest egg surface to enter zona pellucida. Fertilization accomplishes: restoration of the diploid state & activation of the eggs developmental potential: cleavage. Cytoplasm divides into blastomeres blastula (sphere shaped) Blastula has same volume as original zygote, the cells are just getting smaller through division (normal cell size) Has fluid filled cavity on 1 side. Vegetal pole has yolk, slowly divides, immobile, used for food. Animal pole upper half, cells divide rapidly, become mobile: where the blastocoels forms (fluid starts to flow inside cavity, allows cell mov"t to occur for gastrulation. Blastocyst embryo 64 cells, seperates into 2 types: trophectoderm (te) form extra-embryonic tissues (ex/placenta, gastrulation. Inner cell mass (icm) forms embryo proper, source of es cells. Results in 3 germ layers - trilaminar ectoderm, mesoderm, endoderm. Occurs at blastopore 180o from sperm entry (becomes mesoderm) Neural folds form (dorsal) neural tube: organogenesis.
