EVERYDAY SCIENCE

Detailed explanation-1: -A book lung is a type of respiration organ used for atmospheric gas exchange that is present in many arachnids, such as scorpions and spiders.

Detailed explanation-2: -Gas exchange occurs across a thin cuticular interface separating lung gas from hemolymph containing hemocyanin, the respiratory pigment in spiders. spiders possess a rudimentary tracheal sys-tem in addition to book lungs.

Detailed explanation-3: -Spider Breathing Instead breathing takes place through a kind of passive diffusion. Arachnids have two types of “breathing” apparatuses. The first are called book lungs. Although they are referred to as lungs, they have little resemblance to human lungs.

Detailed explanation-4: -Some spiders do not have any book lungs at all, instead, breathe through tracheal tubes like insects. Most other spiders only have one pair of book lungs, this is what makes tarantulas so unique in this segment.

Detailed explanation-5: -Spiders (Araneae) are unique regarding their respiratory system: they are the only animal group that breathe simultaneously with lungs and tracheae. Looking at the physiology of respiration the existence of tracheae plays an important role in spiders with a well-developed tracheal system.