BISC 316 Lecture Notes - Lecture 13: Aortic Arches, Sinus Venosus, Pulmonary Artery

• School: Simon Fraser University
• Department: Biological Sciences
• Course: BISC 316
• Professor: Tammy Mc Mullan

Document Summary

Amniotes: blood cells and vessels arise from mesoderm to form clusters called blood islands. Outer layer differentiates into endothial cells which form tubes. Cells in the center differentiate into blood cells. The cells form a maze of channels. Fusion of the two aorta on the ventral side starbts from the formation of the heart. Posterior portions forms the sinus venosus (sv) Anterios portions forms the atrium (a), ventricle (v), conus arteriosus (ca) Large sinus venosus: common cardinal and hepatic veins. S shaped loop to fit into the thoracic cavity. Heart is partially divided: a, v, ca. Sv opens into right side of the atrium. O2 blood from lung enters the left side of the atrium. Left atrium is completely separated from right atrium. Sv shifted to right; empties into right atrium. Blood on right side goes to the lung. Returning pulmonary blood enters the la ventricle hits spiral valve in different region than the returning ***