BIOL1300 Study Guide - Midterm Guide: Common Hepatic Duct, Gastrointestinal Tract, Surface Ectoderm
Document Summary
Anatomy exam 2: embryonic period weeks 3-8. Begins with formation of the primitive streak within epiblast. Process that establishes the 3 germ layers: ectoderm, mesoderm, endoderm = trilaminar embryonic disk. Mesoderm paraxial mesoderm (somites), intermediate mesoderm, lateral mesoderm. Three shunts: ductus venosus, ductus arteriosus, foramen ovale. Circulatory changes at birth: decrease in right atrial pressure b/c placental circulation is occluded o, changes: closer of r and l umbilical arteries, l umbilical vein, ductus venosus, ductus arteriosus, foramen ovale. Increase in left atrial pressure b/c of increased pulmonary venous return. Remnants created by closure of fetal circulatory structures. Heart tube formation: lateral plate mesoderm (cephalic area of embryo) splits into somatic layer and splanchnic layer = formation of pericardial cavity. Conus arteriosus smooth part of r ventricle. Aortic vestibule smooth part of l ventricle. Sinus venarum smooth part of r atrium. **smooth part of l atrium formed by pulmonary vein incorporations; jxn of trabeculated and smooth parts of r atrium =
