HTHSCI 1H06 Lecture Notes - Lecture 2: Truncus Arteriosus, Aorticopulmonary Septum, Ductus Arteriosus

• School: McMaster University
• Department: Health Sciences
• Course: HTHSCI 1H06
• Professor: Bruce Charles Wainman

Document Summary

Prenatal life: fetus is immersed in amniotic fluid. Postnatal/adult circulatory system - heart is considered a pump. Brings deoxy blood from rv to air sacs (alveoli) in lungs and returns oxy blood from alveoli to la. Pulmonary trunk emerges from rv to the lv and divides into 2 branches. Right pulmonary artery (rpa) to right lung. Left pulmonary artery (lpa) to left lung. They divide until they form capillaries around the alveoli within lungs. Pulmonary arteries are the only that carry deoxy blood after birth. Co2 passes from blood into air sacs - exhaled. Inhaled o2 from passes from air in lungs into blood. Pulmonary capillaries unite to form venules and then pulmonary veins. Pulmonary veins exit lungs and carry oxy blood to la. 2 left and 2 right pulmonary veins enter the la. These veins are the only veins that carry oxy blood after birth. Contractions of lv then eject oxy blood into systemic circulation.