title: Functional venous admixture in the lungs of the turtle, Chrysemys scripta.
abstract: Pulmonary functional venous admixture was determined during forced, unidirectional ventilation with pure O2 and air. At a normal lung volume of 140 ml X kg-1, anatomical shunts (physical bypass of gas exchange surface by the blood) averaged 10% of pulmonary blood flow but it increased to 28% as lung volume declined to 30 ml X kg-1. Diffusion limitation and possibly inhomogeneity in ventilation: perfusion ratio also contributed to a total functional venous admixture of about 25% at normal lung volume.
mesh_terms: D000818:Animals; D008168:Lung / Q000502:physiology*; D008176:Lung Volume Measurements; D010100:Oxygen / Q000097:blood; D011652:Pulmonary Circulation; D011659:Pulmonary Gas Exchange; D012119:Respiration; D014426:Turtles / Q000502:physiology*; D014692:Ventilation-Perfusion Ratio
chemical_list: D010100:Oxygen