FC: Created by: Alena Santos | The Brain
1: My project is all about the Nervous system. In this book, I will explain the cerebrum, the cerebellum, the Medulla Oblongata, neuron(s), and the Spinal Cord. I also will discuss things that may affect the body systems over time. What some injuries may do and what things would harm the body. I also will include how everything works together as one. | Introduction
2: The Cerebrum | The Cerebrum is the composed of both gray and white matter. It's also the largest part of the human brain, and a fissure, a deep groove, divides the cerebrum into two hemispheres. The cortex, or surface area, is folded into ridges called convolutions. The Cortex is the control board of the Nervous System.
3: The Motor Area | Each area of the Cerebral Cortex has a job it must do. The motor area controls the muscles. It's about two inches wide and runs across the brain between the ears. Neurons of each side of the motor area cross over in the brain and connect to the opposite side of the body, which means that if one side of the Cerebrum becomes damaged, the opposite side of the Body may become paralyzed.
4: Cerebrum continued... | Nerve messages that come from the body regarding touch are found behind the motor area. In the rear area of the cerebrum are the sensations of sight. The centers of Speech, hearing, taste, and smell are in the lower areas of the cerebrum. Interception and awareness of all sensations is called consciousness. Many of the Nerve Cells connect to different parts of the Cerebral Cortex, so that various parts of the Cortex can work together. A second layer of cerebrum called the cerebral medulla make many of the connections.
6: The Cerebellum | Below and behind the Cerebrum is the cerebellum. The cerebellum has both layers of white and gray matter and is divided into two hemispheres. Balance and coordination are the main functions of the cerebellum. If the Cerebellum becomes damaged, muscular movements will become unpredictable and jerky.
7: The Medulla | The medulla oblongata is the lowest part of the brain, is attached to the spinal cord, and is composed of white matter and gray matter. Although, the white matter is on the outside, and serves as a pathway for nerve messages coming from the higher parts of the brain. While, the gray matter serves as a switchboard for sensory messages coming to the central nervous system and for outgoing motor messages to some muscle or gland. Many of the crucial functions necessary for life to continue are controlled by certain cells in the Medulla's gray matter, including the rate of breathing, heart beat. and digestion.
8: The Spinal Cord | Spinal Cord: a long bundle of nerves found within the vertebral column. | There are thirty-one pairs of nerves attached to the spinal cord carrying messages to and from the spinal cord, and they reach out to all parts of the body. While, some nerves carry messages to the brain, other nerves carry messages and glands of the body.
9: Neuron(s) | There are three types of neurons. Neurons that carry messages from the sense organs such as the skin, ears, eyes, nose and tongue towards the brain and spinal cord are sensory neurons. Neurons that carry messages from the brain and spinal cord to either a muscle, causing movement, or to a gland, causing secretion are Motor neurons. Neurons that are found within the brain and spinal cord and that serve to connect the sensory neurons to the motor neurons are Association neurons. These three neurons form the wire's of the body's communication system. Sensory, motor, and association neurons keep the brain informed about what is going on in various parts of the body and in the environment around the body, and they also carry messages originating in the brain to the different tissues and organs of the body.
10: Nerves: "wires" in the human nervous system, which are made of tiny wires which carry the messages from one place to another. Neurons: the tiny individual wires made of cells (Nerve cells), also consists of a cell body and several connecting fibers. Cell Body: the control center of the cell and contains the nucleus or center, and is surrounded by cytoplasm. Protoplasm: the essential living matter of all cells. Thread-like fibers: growing out of the cell body and carry the messages from one place to another.
11: Dendrites: fibers that bring messages to the cell body. Axon: one large nerve fiber that carries messages away from the cell body, and at the end opposite to the cell body, it branches into finer branches. End Plates: the finer branches the axon branches into. | Messages will travel in only one direction through a neuron. From the dendrites to the cell body, then along the Axon to the end plate. | The nerve message must travel along the neuron to the end plate, a new message is generated in the next neuron. This message must cross over a space (the synapse).
12: The Synapse: act like one-way valves that keep the message from traveling the wrong way (backwards) along the wires. Myelin Sheath: a white fatty substance that some neurons are covered in, and serves to insulate the neuron and keep the message from running on the wrong wire. White Matter: commonly referred to as the neurons that have the myelin sheath. Gray Matter: the neurons lacking the myelin sheath. Neurilemma: axons that are enclosed in a tube-like structure, and it makes it possible for a cell body that might have lost its axon to grow another one.
13: A Neuron
14: Damages | Paralyzing: Spinal Cord- the point below the injury. Cerebrum- if one side becomes damaged the opposite side of the body may be paralyzed. | Drugs: kills cells in the brain that can never be grown or healed back. | Brain Cancers: Primary Brain cancer- starts in brain. Metastatic brain cancer- starts somewhere else and moves to the brain
15: Damages | Brain tumors: With no cancer cells or with cancer cells that grow quickly, but no one knows the exact reasons for brain tumors. | All damages to the brain or involve the brain are very serious and are very hard to deal with. Many families have suffered because of brain damages as simple as someone forgetting a helmet to an unknown reason to smoking or doing drugs.
16: Brain Tumors | Symptoms: -Headaches -Nausea and vomiting -Changes in ability to hear, see, or talk -Problems with balance or walking -Problems with thinking or memory | Symptoms continued: -Muscle Jerking or twitching -Numbness or tingling in arms or legs
17: Brain Cancer | Symptoms: -Headaches -Weakness -Clumsiness -Difficulty walking -Seizures -Changes in concentration, memory, and alertness -Nausea and vomiting | Other symptoms: -Difficulty with speech -Gradual Changes in intellectual and emotional capacity
18: The Brain Working Together | Everything works together. The brain controls movements, emotional, and intellectual thinking. The brain is always working even if you are sleeping. Your brain never stops. The one thing the brain is not involved in is Reflexes.
19: The Reflex | Reflex means to "turn back". Doctors check your reflex by tapping your kneecap with a rubber hammer, your leg then jerks up as a reflex. If you put your hand on a hot stove your hand pulls away, this is a reflex too. A reflex is involuntary and does not need to be taught. When the doctor tap your knee a nerve message is carried to the spinal cord by a sensory neuron. An association neuron then passes the nerve message to a motor neuron. the motor neuron goes down the leg to the muscle, then the lower leg is jerked up. This whole action is called a reflex arc.
21: The End