CIRCULATORY ROUTESCIRCULATORY ROUTES

1.1. Systemic circulationSystemic circulation• Arteries carry oxygenated blood to all body Arteries carry oxygenated blood to all body

tissue (except alveoli of lungs); veins tissue (except alveoli of lungs); veins deoxygenated blood (with CO2) back to deoxygenated blood (with CO2) back to heartheart

• Major vessels: aorta, superior/inferior vena Major vessels: aorta, superior/inferior vena cavacava

2. Pulmonary circulation2. Pulmonary circulation– ShorterShorter– Arteries: thinner walls, less elastic tissue, Arteries: thinner walls, less elastic tissue,

larger diameter (resistance?)larger diameter (resistance?)– Deoxygenated blood (CO2 rich) to lungs and Deoxygenated blood (CO2 rich) to lungs and

oxygen-rich back to heartoxygen-rich back to heart– Pulmonary trunk, pulmonary arteries/veinsPulmonary trunk, pulmonary arteries/veins

3. Hepatic portal circulation3. Hepatic portal circulation– Carries venous blood (nutrient-rich) from Carries venous blood (nutrient-rich) from

gastrointestinal tract to livergastrointestinal tract to liverLiver: glucose Liver: glucose glycogen (storage), detoxifies, glycogen (storage), detoxifies, destroys bacteriadestroys bacteria

4. Coronary route:4. Coronary route:• Supplies oxygen/nutrients to heart cellsSupplies oxygen/nutrients to heart cells• Coronary arteries branch from ascending Coronary arteries branch from ascending

aorta and encircle heart, into capillaries, then aorta and encircle heart, into capillaries, then into coronary veins (drain deoxygenated into coronary veins (drain deoxygenated blood into right atrium)blood into right atrium)

5. Fetal circulation5. Fetal circulation– PlacentaPlacenta– Umbilical cord: 2 arteries (fetal waste), 1 vein Umbilical cord: 2 arteries (fetal waste), 1 vein

(fetal nutrients)(fetal nutrients)– Ductus venosus: by-passes (skips) most liverDuctus venosus: by-passes (skips) most liver– Foramen ovale: between atria; by-pass lungsForamen ovale: between atria; by-pass lungs– Ductus arteriosus: connects trunk to aorta: by-Ductus arteriosus: connects trunk to aorta: by-

pass lungspass lungs

WARNING: placenta on next slide

PLACENTA WITHPLACENTA WITHUMBILICAL CORDUMBILICAL CORD