Biology 1st Edition by Jerome Krueger, Kendra Hill, Robert Noyd

Exercise 4

Spiders have two narrow slits on their lower abdomen that each open to a respiratory structure called a book lung. Book lungs consist of a stack of air-filled hollow "pages," or thin narrow air pockets, that extend into a blood-filled chamber ( Fig. ). Within these air pockets, oxygen and carbon dioxide are exchanged with the spider's blood. Refer to factors in Table to explain how the book lung increases the rate of diffusion.
Figure The book lung of spiders.


Table Factors Influencing Gas Exchange