CIRCULATORY ADAPTATION TO DIVING IN THE FRESHWATER TURTLE.
The heart of the freshwater turtle has a functional ventricular septal defect. In ambient air there is some shunting of blood from the left to the right ventricle through the defect. During prolonged diving or N(2) inhalation, the shunt is reversed and blood from the tissues bypasses the lung and enters the aorta directly. This adaptation appears to be based on the exclusive use of anaerobic glycolysis as an energy source during prolonged diving.
D000064:Acclimatization; D000220:Adaptation, Biological; D000222:Adaptation, Physiological; D000818:Animals; D001011:Aorta; D005075:Biological Evolution; D001775:Blood Circulation; D050260:Carbohydrate Metabolism; D004242:Diving; D004395:Dye Dilution Technique; D005618:Fresh Water; D006321:Heart; D006345:Heart Septal Defects, Ventricular; D006352:Heart Ventricles; D008168:Lung; D008660:Metabolism; D011652:Pulmonary Circulation; D012104:Reptiles; D012106:Research; D014426:Turtles
ADAPTATION, BIOLOGICAL; BLOOD CIRCULATION; CARBOHYDRATE METABOLISM; DIVING; DYE DILUTION TECHNIC; EVOLUTION; EXPERIMENTAL LAB STUDY; HEART SEPTAL DEFECTS, VENTRICULAR; METABOLISM; PULMONARY CIRCULATION; REPTILES