how do spiders breath?

Question

I saw a show about respiration on pbs and it didn't answer this, but got me wondering about it...

please no off topic answers or guesses.

Answer 1

Spiders obtain their oxygen through four respiratory organs located on the underside of their abdomens. These organs are arranged into two pairs, an anterior pair at the very front end of the abdomen, and a posterior pair behind the anterior pair. Each of these can take one of two forms, book lungs or tracheae. In some spiders both pairs are book lungs, in a few both are tracheae, but in most cases the anterior pair are book lungs and the posterior pair are tracheae.

Book lungs consist of stacks of between 10 and 80 flattened hollow discs. These are bathed in haemolymph (the spider's equivalent of blood), and the shape of the book lung maximises the surface area at which gaseous exchange can occur. Air enters a hole in the spider's abdomen called a spiracle and diffuses into the book lungs. Since the spider's heart is continually pumping deoxygenated haemolymph through the book lungs, the concentration of oxygen in the air in the book lungs is always higher than in the haemolymph, and therefore oxygen will move from the air into the haemolymph down an oxygen gradient. The oxygenated haemolymph is then pumped to the organs where it delivers its oxygen.

Tracheae consist of a system of branching tubes, which extend from the spiracles to deliver oxygen directly to the organs. It is generally assumed that there has been a gradual evolutionary change from book lungs to tracheae, possibly in response to the need to conserve water, since a great deal can be lost across the large surface area of the book lung. Although doubts have been raised about whether tracheae could evolve directly from book lungs, the book lungs of some spiders have a small number of greatly elongated chambers, and these have been interpreted as an evolutionary intermediate in the evolution of tracheae from book lungs

Answer 2

There are at least two, possibly three, methods.
Some spiders, such as tarantulas and their
relatives, have two pairs of book lungs. These open on the underside of the abdomen just behind the waist. They consist of many thin flat
leaves with air spaces between.

Most other kinds of spiders have either one pair
of book lungs and a set of tracheae or tracheae
only. The tracheae are thin hollow tubes that lead
air to various parts of the body. They are very well
developed in some spiders, less so in others.

It is possible that some of the very tiny spiders, a
few of which are only one millimeter or less in
length, may exchange gases directly through the
cuticle, at least in part.

Answer 3

Yes they do but its not like ares. Look at Wikipedia link there and its will explain it.

Answer 4

I have no idea, I hate those things and I try to stay away from them.