Pig Heart Dissection
Materials: ★★★ Requires materials not commonly found in school laboratories
Difficulty: ★★☆ Can be done by science teachers
Safety: ★★☆ Some safety precautions required to perform safely
Categories: Body Systems, Dissections
Alternative titles:
Summary
Use a preserved pig heart to identify external landmarks and internal chambers, valves, and vessels. Trace the path of blood through the right and left sides to connect structure with one-way flow and double circulation.
Procedure
Links
Variations
Inject dyed water through the vena cava or pulmonary veins to visualize valve function and flow paths.
Compare pig, sheep, or beef hearts for size and wall thickness differences relative to body size and lifestyle.
Map coronary circulation by threading fine tubing into the coronary ostia from the aorta.
Safety Precautions
Wear gloves and a lab apron; avoid contact with preservatives and do not touch your face.
Use scissors for most cuts; if a scalpel is required, make shallow strokes on the tray and cut away from fingers.
Treat all tissues and fluids as potential biohazards; keep food and drink out of the lab.
Dispose of biological waste and blades in approved containers; disinfect tools and benches after the lab; wash hands thoroughly.
Questions to Consider
Why is the left ventricular wall thicker than the right? (It must generate higher pressure to drive systemic circulation.)
What prevents backflow from the ventricles into the atria during systole? (Atrioventricular valves—tricuspid and mitral—supported by chordae tendineae and papillary muscles.)
Where are semilunar valves located and what is their role? (At the bases of the pulmonary trunk and aorta; they prevent backflow into the ventricles during diastole.)
Which vessels carry oxygen-poor vs. oxygen-rich blood entering and leaving the heart? (Venae cavae and pulmonary artery carry oxygen-poor; pulmonary veins and aorta carry oxygen-rich.)
What structural feature supplies oxygen to the heart muscle itself? (Coronary arteries arising from the aortic root via coronary ostia.)
How does double circulation improve oxygen delivery compared with single circulation? (It separates pulmonary and systemic circuits, maintaining higher systemic pressure without damaging lung capillaries.)
What is the function of the pericardial cavity and fluid you observed around the heart? (They reduce friction as the heart beats and help stabilize position.)