Method of Breathing of Porcupines

Areobic respiration through the use of internal organs which filter oxygen and nitrogen from air and allow it into the blood stream while filtering out carbon dioxide and expelling it from the body, through an external orifice which functions alternatingly as a intake valve for the incoming air and an exaust valve for the expelled waste. The valve exits the body in three places: either nostril and the mouth, which also functions as the orifice through which food is consumed.