Lab 6: Dissection of the Fetal Pig, The Circulatory System

Question 1

foramen ovale

Answer 1

The foramen ovale is a normal cardiac structure found in all newborns and can be best described as a “door” between the right and left atria.

The foramen ovale is essential for proper fetal circulation, directing oxygenated, nutrient-rich blood from the placenta, preferentially to the developing fetal brain. During fetal life, the “door” is open, and blood passes from the right to left atrium. However, with separation from the placenta and with the first few breaths, the left atrium fills with blood returning from the lungs and closes the “door.”

During the first years of life, the foramen ovale seals shut and becomes a true wall that separates the right and left atria.

Question 2

Pathway of Deoxygenated Blood

Answer 2

Body&raquo_space; Posterior Vena Cavae&raquo_space; Right Atrium&raquo_space; Tricuspid Valve&raquo_space; Right Ventricle&raquo_space; Semilunar Valve&raquo_space; Pulmonary Artery&raquo_space; Left and Right Lungs

Question 3

Pathway of Oxygenated Blood

Answer 3

Lungs&raquo_space; Pulmonary Veins&raquo_space; Left Atrium&raquo_space; Bicuspid Valve&raquo_space; Left Ventricle&raquo_space; Aortic Arch&raquo_space; Body