Putrefaction is made up of biological decomposition of organic matter; associated with anaerobic conditions. Putrefaction occurs with the deterioration of organic substances through the activities of biological organisms that results in a foul stench. Putrefaction takes place about every two to three weeks after the passing of an organism, with its 5th stage bringing about rigor mortis. This process also brings about the dissolvement of tissues, proteins, organs, and other important human body parts. Nitrogen is reprocessed from dead animals as a result of putrefaction as well.