Neurons+-+ES

=Introduction=

You’re walking through your kitchen, and as you pass the stove, your forearm brushes against a hot pan that just came out of the oven. You jump back immediately and start to rub your burning arm with your hand. Although you might not realize it, your nerve cells are hard at work allowing you to do this. Nerve cells send messages, called **impulses**, to the brain which then are sent to different parts of your body. Parts called **dendrites** and **axons** on the cell body of a **neuron** (neurons build up nerve cells) help the process of passing this message. Without this process, all movement would eventually be impossible. The article "What is Lou Gehrig's Disease" says, “Things that we do every day- like breathing, walking, running, lifting stuff and even reaching for a glass of water- are controlled by the neruomuscular system.”

toc =Function of a Nerve Cell= The nerve cells in your body have very important functions, that are needed for human life. Neurons (otherwise known as nerve cells) pass electrical messages, called impulses, that tell your body to move, sense, think and feel (“Neurons”).Think of nerve cells like wires in a computer, sending and receiving messages to help the whole system work. The first thing that happens in this process is when something in the outside environment occurs. For example, your skin brushing against burning pan. What happens here is your nerve cells send a message to your brain, telling your brain that the pan is hot. Then, your brain will send another impulse back through your nerve cells, telling your muscles and joints to move yourself away from the pan. But in order for this process to happen, you will need two different kinds of nerve cells, the motor neuron and the sensory neuron. Sensory neurons are the nerves that send a message to your brain about what’s happening outside. Motor neurons will take an impulse from your brain and send messages to your muscles, telling them to move ("The Nervous System"). Both types of these nerve cells build up a big portion of your body, known as the nervous system. According to the article “The Nervous System”, your nervous system is built up of your brain, your spinal cord and the millions of nerves that make up your body. But even inside those nerve cells, there are specialized parts that help the neuron perform this task.

Click here to see impulses being passed between multiple neurons:

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=Structures of A Nerve Cell= Nerve cells are one of the longest cells, so they can send impulses all over your body. To help the nerve cell perform this function of transmitting impulses, there are many specialized structures within a nerve cell. Like the members of an assembly line, different people (or in this case structures) are needed to do different jobs. This includes a structure within a neuron called a dendrite. Dendrites are threadlike extensions that help carry impulses towards the cell body. Dendrites are in bundles, and they take in impulses. Dendrites extend off of the cell body, which holds the nucleus and its also attached to the axons (Padilla et al 178). Since dendrites are long and thin, they can easily receive messages from other neurons. But what sends messages to the dendrites? The answer, is axons. The axon is longer and thicker than dendrites, but it’s job is similar. According to the online article “The Nervous System”, axons send out messages, t other nerve cells, while dendrites receive them. Think of dendrites as a net, and the axon is a person throwing something into it. To help the axon do its job, it has a coating of a substance called myelin. Myelin is " a fatty substance that wraps around nerve fibers and serves to increase the speed of electrical communication between neurons, "(Myelin: An Overview). This layer of myelin quickens the speed at which impulses can go through the axon (Brain Pop “Neurons”). Interestingly enough, the axon of one cell and the dendrites of another cell do not touch when having this exchange. There is a small space between them called the synaptic cleft (“Neurons”). All of these structures allow nerve cells to perform their function, which is vital to be able to live a normal life.



=Why Nerve Cells are Important?= Thanks to the structure of the nerve cell, we are able to do things like jump, walk, run and blink. “Without the nervous system...people would not experience joy at seeing an old friend or automatically pull their hand away from a hot stove,” ("The Brain and Nervous System"). This is because the neurons in your body control all of your movements. So what would life be like without nerves? Over time, your muscles would stop working, and eventually you wouldn’t be able to move. This is a reality for some people. These people have a disease called Lou Gehrig’s Disease (also known as ALS). Lou Gehrig’s Disease (named after famous Yankee player Lou Gehrig) damages motor neurons, which control your muscle movements, in the spinal cord and brain. In most cases this damage results in your motor neurons shrinking until they become non existent. This will result with the patient not being able to move, because your motor neurons control the movement of your muscles. Although, your ability to feel, smell, hear and see will remain intact, because they are controlled by your sensory neurons ("What is Lou Gehrig's Disease?"). Symptoms of Lou Gehrig’s include muscle weakness, cramping and twitching of the muscles. There is currently no cure to ALS, although there are medicines available to control the symptoms.On another note, Lou Gehrig’s Disease is not contagious, and many people that have it still manage to have a normal life. For instance, a man named Stephen Hawking has been living with ALS for 50 years. He is in a wheelchair, and a special computer to speak and write says, “[ALS] has not prevented me from having a very attractive family, and being successful in my work…”

To see a diagram of the nervous system and read more about it, check out this website:

http://www.livescience.com/27975-human-body-system-the-nervous-system-infographic.html

To find out more about ALS, click here:

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=Conclusion= Your body is a giant computer. All of the 100 billion nerve cells within it work like wires to keep the computer moving. Impulses send information to the brain, which allow the computer to do what you ask it to. All of the different structures of a nerve cell (or in this case a wire) allow these messages to be sent. A computer without wires is incapable of working. So think, where would you be without nerve cells?

=References=

“The Brain and Nervous System.” Human Diseases and Conditions, www.humanillnesses.com/Behavioral-Health-A-Br/The-Brain-and-Nervous-System.html. Accessed 30 Jan. 2017. Coolidge-Stolz, Elizabeth, et al. Human Biology and Health. Boston, Pearson, 2009. Dowshen, Steven, editor. “Lou Gehrig’s Disease.” KidsHealth.org, Jan. 2016, kidshealth.org/en/kids/als.html. Accessed 30 Jan. 2017.

Kirkwood, Caitlin, author. "Myelin: An Overview" Brainfacts.org, 24 March 2015,

http://www.brainfacts.org/brain-basics/neuroanatomy/articles/2015/myelin/ Accessed 3 Feb. 2017

Krane, Elliot. “How Do Nerves Work?” TEDEd, ed.ted.com/lessons/how-do-nerves-work. Accessed 30 Jan. 2017. "Lou Gehrig". //Wikipedia, 2017,// https://en.wikipedia.org/wiki/Lou_Gehrig. Accessed 3 Feb. 2017. "Nerve Impulse Animation" //You Tube,// uploaded by Daniel Hausmann __ [] __ "The Nervous System" BBC, 2014, http://www.bbc.co.uk/schools/gcsebitesize/science/ocr_gateway_pre_2011/ourselves/3_keeping_in_touch5.shtml. Accesses 3 Feb. 2017. “Nervous System.” PowerKnowledge Life Science, Rosen Publishing, www.pklifescience.com/article/435/nervous-system. Accessed 30 Jan. 2017. “The Nervous System.” Ducksters, TSI (Technological Solutions Inc.), Jan. 2016, www.ducksters.com/science/nervous_system.php. Accessed 30 Jan. 2017. “The Nervous System.” YouTube, uploaded by Makemegenius, 28 Feb. 2012, www.youtube.com/watch?v=sjyI4CmBOA0. Accessed 30 Jan. 2017. “Neurons.” BrainPOP, www.brainpop.com/health/bodysystems/neurons/. Accessed 30 Jan. 2017. Silverstein, Alvin, and Virginia Silverstein. “Nervous System.” The New Book of Knowledge. Scholastic Grolier Online, nbk.grolier.com/ncpage?tn=/encyc/article.html&id=a2020640- h&type=0ta. Accessed 30 Jan. 2017. Toro, Ross, artist. "Diagram of the Human Nervous System" livescience.com 18 March 2013, http://www.livescience.com/27975-human-body-system-the-nervous-system-infographic.html Accessed 3 Feb. 2017.

“Types of Neurons (Nerve Cells).” Neuroscience for Kids, Eric H. Chudler, faculty.washington.edu/chudler/cells.html. Accessed 30 Jan. 2017.