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The Nervous System Unit One: Source UNIT ONE THE NERVOUS SYSTEM Unit One: The Nervous System UNC-CH Brain Explorers May be reproduced for non-profit educational use only. Please credit source. 3 UNIT ONE THE NERVOUS SYSTEM Unit One: The Nervous System UNC-CH Brain Explorers May be reproduced for non-profit educational use only. Please credit source. 4 THE NERVOUS SYSTEM UNIFYING SUMMARY KEY POINTS CONCEPTS FULL BODY TRACING • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Models help us understand and In the Full Body Tracing students • All our thooughts, movements, explain the world.* work together as a class to create sensations and emotions are • Systems are made of parts which a model of the nervous system. controlled by the nervous system. connect to create the whole.* The outline of a student’s body is • We have a Central Nervous • The brain receives informational traced on a large piece of paper. System (brain and spinal cord) signals from all parts of the body. A cardboard cut out of the brain and Peripheral Nervous System The brain sends signals to all parts and spinal cord are placed in the (nerves extending from the spinal of the body to influence what they outline to represent the central cord to limbs, trunk, face, organs do.* nervous system. Two colors of and throughout.) • Humans have systems for yarn, representing the motor and • Sensory nerves communicate digestion, circulation, movement sensory nerves, are used to create information from the body to the and coordination. These systems motor and sensory pathways of brain and motor nerves, from the interact with one another.* the peripheral nervous system. brain to the body. • Describe the basic structure and function of human body system.* CLAY BRAINS • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Models help us understand In the Clay Brain lesson students • The brain is divided into the complex structures. Such work individually to create a scale left and right hemispheres which representations can never be exact model of the human brain and control opposite sides of the body. in every detail.* learn about the functions of each • Other major brain parts • Children can begin to view the part.. include the corpus callosum, the cerebellum and the brain stem. body as a system, in which parts Each has a special function: influence one another. Parts do keeping the body alive, keeping things for other parts and for the the body balanced and allowing organism as a whole.* body systems to communicate. • Describe the basic structure and function of human body system.** MAGIC WAND • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Scientific inquiry includes the process of following specific steps The Magic Wand lesson teaches • The left hemisphere controls the to verify findings. Students practice localization of function of the right side of the body; the right skills of observation, collecting and cortex. Students reenact the hemisphere controls the left side. recording data, analyzing results experiments of Dr. Wilder Pen- • Sensory and motor function are and forming conclusions.* field. They observe the move- controlled by specific regions of • Humans have distinct body ments and sensory responses of a the cerebral cortex. structures. Our brain structures human subject being stimulated correspond to different body and observe what parts of the functions.* brain correspond to different • Describe the basic structure and sensations and movements. function of human body system.** * Source: National Science Standards ** Source: National Health Standards Unit One: The Nervous System UNC-CH Brain Explorers May be reproduced for non-profit educational use only. Please credit source. 5 Lesson Overview Engage (5 minutes) • Pairs of students practice closing eyes and being touched silently by a partner. How do you know where you were touched when nothing was said? • During discussion, two student volunteers create a full-body tracing outline. (One traces the other who is lying on paper.) Explore (10 minutes) • Discuss how we know we feel something; use a question and asnswer method to discuss the role of the nervous system in the experience of being touched. Hand out human body outlines. Explain (20 minutes) • Explain motor and sensory nerves, central and peripheral nervous system. Hang the tracing and have volunteers add central and then peripheral nervous systems to a large outline of the human body. Students recreate the model at their desks. Expand (10 minutes) • Think of other examples of movement and touch sensations. How does our nervous system function within our bodies? Evaluate (10 minutes or while assembling large diagram) • Students draw and label the nervous system on their handout of a human body. Label the three major parts of the nervous system. • Part II: Complete or write sentences using the words motor nerves and sensory nerves. LESSON 1 Supplies: Two contrasting colors of yarn, a roll of paper, tape, two contrasting color markers and a student handout per student. Unit One: The Nervous System UNC-CH Brain Explorers May be reproduced for non-profit educational use only. Please credit source. 6 Heres an example of a fi nished full-body image, complete with the nervous system created by a fourth grade class. FULL BODY TRACING BODY FULL Color key Nerves to both arms and legs This model can be simplifi ed according to time constraints. Be sure to include one motor nerve, one sensory nerve, and their labels. Unit One: The Nervous System UNC-CH Brain Explorers May be reproduced for non-profit educational use only. Please credit source. 7 Background The Full Body Tracing The first lesson of this unit introduces different parts of the nervous system by constructing a model of the nervous system with a full body tracing. Students will learn how the brain sends and receives messages via the nervous system. Any part of the body that can move or feel is connected to the nervous system. The Central Nervous System (CNS) is made up of the brain and the spinal cord. The vertebrae of the spine encase and protect the soft neural tissue of the spinal cord, just like the skull protects the brain. The motor and sensory nerves running throughout the body make up the Peripheral Nervous System (PNS). The PNS sends message to and from the CNS. The CNS controls the body by sending messages that flow through the motor nerves to control muscles. Sensory nerves relay messages about touch, pressure, temperature, pain, sound, vision, smell, and taste to the CNS. Thus, motor nerve messages travel from the CNS out to the muscles in the body and sensory nerve messages travel from nerve endings in the body back in to the CNS. Motor and sensory nerve messages do not share the same pathways in the body. They are like one-way streets, traveling in only one direction. Another division of the Peripheral Nervous System is the Autonomic Nervous System (ANS), which usually controls muscles without conscious awareness. These muscles control heartbeat, breathing, blinking, pupil dilation, and digestion. The specific locations in the brain that control the different parts of the body will be discussed in the following lessons. FULL BODY TRACING BODY FULL Unit One: The Nervous System UNC-CH Brain Explorers May be reproduced for non-profit educational use only. Please credit source. 8 Name _______________________ Class _______________________ The Nervous System 1. Choose two colors of marker or pencil. 2. Draw lines with arrows on them showing motor nerves carrying messages out to the muscles, and sensory nerves carrying information from the outside world to the brain. 3. Complete the color key below with your colors and labels (motor nerve, sensory nerve). This person is looking to their left. Which hemisphere do we see? Key Full Body Tracing: Summary STEP 1: Choose a stu- dent to be traced and one to do the tracing. STEP 2:While this is happening, discuss the experience of touch. How do we know when we are touched if we do not see it happen? STEP 3: Volunteers place paper models of the brain and spinal cord in the full body tracing while the class begins fi lling in their own scale version on a handout. STEP 4: At their desks, students complete a 2D version of the model be- ing created at the front of the room. FULL BODY TRACING BODY FULL Unit One: The Nervous System UNC-CH Brain Explorers May be reproduced for non-profit educational use only. Please credit source. FULL BODY TRACING BODY FULL STEP 5: Add yarn and labels to the model. Use one color for the motor nerves and another color for sensory nerves. STEP 6: Add arrows showing the direction the messages travel. STEP 7: Create a color key and label the Central and Peripheral Nervous Systems. Vocabulary Terms: Brain Spinal Cord Nerves Nervous System Motor and Sensory nerves Assessment: Students complete a scale drawing of the nervous system with parts labeled, arrows and a color key. Unit One: The Nervous System UNC-CH Brain Explorers May be reproduced for non-profit educational use only. Please credit source. Lesson Overview Always a popular activity, the clay brains lesson introduces the parts of the brain and the function of the parts. This activity challenges students to really study the 3D brain models and become familiar with the parts of the brain through simultaneous tactile and auditory experiences. As students hear about the parts of the brain, they also shape them with their hands. Engage (10 minutes) • Display a model human skull. 1/4 inch thick skull protects the brain; protect your skull and brain by wearing a helmet. • Display several life-sized brain models. Introduce names for the different structures of the brain. • Point out the Greek and Latin roots. • Students will be making brain models out of clay! Explore/Explain (25 minutes) • Pass out supplies to each student. • Student volunteers read each paragraph.
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