Because of the chemical nature of impulse and the axon-dendrite structure. Because of the chemical nature of impulse and the axon-dendrite structure. http://www.biologymad.com/nervoussystem/nerveimpulses.htm (Best technical explanation and excellent graphics and animations)
Newborns may sneeze, and this is typically attributed to the irritation of their nasal passages. The most common irritants, explains Dr. Iannelli, are smoke (and simply smoking outside is not enough), animal dander from pets in the house, dust mites, and mold.
Why Cats Sneeze. An occasional sneeze in a cat is normal and no real cause for alarm. Just as in humans, sneezing in cats is an explosive release of air through the nose and mouth - often the bodyâs response to irritants in the nasal passages. Sometimes, excitement or movement can bring on sneezing in cats.