打喷嚏是人们再熟悉不过的现象了。鼻子里进了异物我们会打喷嚏,得了风寒流感我们会打喷嚏,甚至有些人被太阳照到也会打喷嚏。其实打喷嚏只不过是人和动物都会有的一种生理反射行为。当人体鼻黏膜上的感受器感知到异物后,会经过三叉神经传导到脑部。然后我们会有鼻子发酸、发痒的感觉,之后便会不由自主地吸气、张嘴,然后从嘴和鼻腔里同时高速(可达每小时50千米)排出气体。 Sneezing is a familiar phenomenon. There’s a foreign body into the nose We’ll sneeze and get a cold flu We’ll sneeze and even some people will sneeze when the sun shines. In fact, sneezing is just a physiological reflection behavior that people and animals have. When the human nasal mucosa receptors perceive foreign body, it will be transmitted to the brain through the trigeminal nerve. Then we have a sore, itchy sensation in our nose, and then involuntarily inhale, open our mouth and then expel the gas at high speed (up to 50 km / h) from the mouth and nose.