Compared with external respiration, the gases now move in opposite directions.

与外呼吸相比，气体现在向相反的方向移动。

External respiration refers to gas exchange across the respiratory membrane in the lungs.

外呼吸是指肺部呼吸膜上的气体交换。

In the lineage of true scorpions, external respiration organs called " book-gills" were adapted into internal " book-lungs" .

在真正的蝎子谱系中，称为“书鳃”的外部呼吸器官被改编成内部“书肺”。

Gas exchange in the lungs is referred to as external respiration as one side of the respiratory membrane - that is, the alveolar air - is actually outside of the body.

肺中的气体交换被称为外呼吸，因为呼吸膜的一侧（即肺泡空气）实际上在体外。