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.
Sneezes protect your body by clearing the nose of bacteria and viruses, Kao explains. When something enters your nose or you encounter a trigger that sets off your sneeze center in your brain, located in the lower brain stem, signals are rapidly sent to tightly close your throat, eyes, and mouth.Next, your chest muscles vigorously contract, and then your throat muscles quickly relax.ut signals traveling along nerves can take slightly different paths to and from the brain, resulting in different sneeze scenarios from person to person. It's a nerve transmission that tells your brain something is in your nose that needs to come out, Kao tells WebMD. 2. Sneezing helps keep your body safe.