7.1 Introduction to the Nervous System
Fig.7-1 The Nervous System
Fig.7-2 The Brain
(https://www.daowen.com)
Fig.7-3 The Neuron
Task 1 Fill in the numbered blanks according to the video.
The nervous system is the control center for the body.It 1.________all other body systems.It is the source of our thinking，movement，emotions，and it makes us unique as 2.________.In order to do this，the nervous system has three major functions.First，it provides us all of the 3.________functions，including our consciousness and our cognitive decision-making abilities；it also provides our 4.________functions，such as taste，touch，and sight，which allow us to respond to stimuli in our daily lives.There are two types of stimuli：an 5.________，which is a trigger that occurs inside the body，such as a viral infection；and an external stimulus，which is a trigger that occurs outside the body，such as changes in the environment.The last major function of the nervous system includes our basic motor function，which is our 6.________.These functions of the nervous system，along with other body systems，help the body to maintain homeostasis and 7.________.Homeostasis is crucial to our ability to live long and healthy lives.For example，the average body temperature is 98.6℉，and if this temperature goes either above or below the average，then we become at risk for illness.To stop this from happening，the nervous system helps to regulate our body temperature and thus maintain balance.At this point，let’s talk a bit about the basic structure of the nervous system so that you are familiar with what’s to come.The structure of the nervous system encompasses various divisions.The two primary systems are the central nervous system（CNS）and the 8.________nervous system（PNS）.The central nervous system includes the brain and the 9.________，and the peripheral nervous system includes a complex network of nerves that span the entire body.Finally，the nerve cell，also known as the 10.________，is the basic building block for all nervous system structures.
