Final answer:
Terrestrial spiders breathe through book lungs, which are internal stacks of tissue with air spaces that facilitate gas exchange with the air. These structures are different from aquatic spiders' gills and insects' tracheal systems.
Step-by-step explanation:
How Terrestrial Spiders Perform Respiration
Terrestrial forms of spiders perform respiration primarily through specialized structures called book lungs. These book lungs are made up of a vertical stack of hemocoel wall tissue that closely resembles the pages of a book, alternating between tissue and air pockets. This construction allows air to come into contact with a large surface area of tissue, greatly improving the efficiency of gas exchange. Unlike their aquatic counterparts, like the diving bell spider, which exchanges gases through gills, terrestrial spiders do not utilize this method. Instead, they rely on their book lungs to extract oxygen from the air in their terrestrial habitats.
Some terrestrial arthropods, such as insects, have a different system called a tracheal system. This system consists of a network of tubes called tracheae that intake air through openings known as spiracles. However, spiders do not use a tracheal system; their reliance is solely on the function of their book lungs for respiration.