Mitochondria have an important role in cellular respiration through the production of ATP, using chemical energy found in glucose and other nutrients. Mitochondria are also responsible for generating clusters of iron and sulfur, which are important cofactors of many enzymes
Well, considering that seagulls, bears, and cows are warm blooded mammals, and spiders are arachnids with an exoskeleton, I'm willing to bet that spiders are ectothermic. And isn't the word exothermic?
