Why the Nervous System Is Important? Gives us our sense of touch, pain, heat, and cold. Gives us our sense of touch, pain, heat, and cold. Gives us movement. Gives us movement. The brain sends impulses to the muscles to cause movement The brain sends impulses to the muscles to cause movement Controls our involuntary organs such as the heart, lungs, digestive tract, and skin Controls our involuntary organs such as the heart, lungs, digestive tract, and skin

Components of the Nervous System ● Brain- Control center –Spinal Cord- Highway for messages from the brain to the body. –Medulla Oblongata- Controls heart rate, blood pressure, breathing, swallowing, and vomiting. –Reticular Formation- Plays a role in consciousness.

Anatomy and Physiology The Nervous System contains millions of nerve cells or neurons that respond to stimuli (such as touch, sound, light, and so on), conduct impulses, and communicate with each other (and with other types of cells like muscle cells) The Nervous System contains millions of nerve cells or neurons that respond to stimuli (such as touch, sound, light, and so on), conduct impulses, and communicate with each other (and with other types of cells like muscle cells) A neuron is located in the cell body and extend from processes called dendrites and axons A neuron is located in the cell body and extend from processes called dendrites and axons Dendrites conduct impulses toward the cell body and axons conduct impulses away from the cell body Dendrites conduct impulses toward the cell body and axons conduct impulses away from the cell body

Key Terms Neuron-a specialized, impulse-conducting cell that is the functional unit of the nervous system Neuron-a specialized, impulse-conducting cell that is the functional unit of the nervous system Nerve tissue- tissue composed of neurons Nerve tissue- tissue composed of neurons Neuroglia- a class of cells in the brain and spinal cord that form a supporting strucuture for neurons Neuroglia- a class of cells in the brain and spinal cord that form a supporting strucuture for neurons Cell body- the compact area of a nerve cell that constitutes the nucleus surrounding cytoplasm Cell body- the compact area of a nerve cell that constitutes the nucleus surrounding cytoplasm Axon- the appendage of the neuron that transmits impulses away for the cell body Axon- the appendage of the neuron that transmits impulses away for the cell body Dentrite- the branching process of a neuron that conducts impulses toward the cell Dentrite- the branching process of a neuron that conducts impulses toward the cell Synapse- region where nerve impulses are transmitted Synapse- region where nerve impulses are transmitted

Neurons and Synapses Neuroglial or glial cells general functions: Neuroglial or glial cells general functions: 1 - forming myelin sheaths 2 - protecting neurons 3 - regulating the internal environment of neurons in the central nervous system 1 - forming myelin sheaths 2 - protecting neurons 3 - regulating the internal environment of neurons in the central nervous system Synapse- point of impulse transmission between neurons Synapse- point of impulse transmission between neurons This impulse impulse is transmitted by the release of chemicals called chemical transmitters This impulse impulse is transmitted by the release of chemicals called chemical transmitters

Picture of Synapse

Types of Neurons Multipolar neurons-have many processes that extend from the cell body: lots of dendrites plus a single axon, they cause activity and communication Multipolar neurons-have many processes that extend from the cell body: lots of dendrites plus a single axon, they cause activity and communication Unipolar neurons- have but one process from the cell body. That single, short process splits into longer a dendrite plus an axon. Unipolar neurons are sensory neurons Unipolar neurons- have but one process from the cell body. That single, short process splits into longer a dendrite plus an axon. Unipolar neurons are sensory neurons Bipolar neurons - have two processes - one axon & one dendrite. These neurons are also sensory. Bipolar neurons - have two processes - one axon & one dendrite. These neurons are also sensory.

Neuron Cell

Central Nervous System The brain plays the main role in body functions The brain plays the main role in body functions Spinal cord is connected to brainstem Spinal cord is connected to brainstem The basic unit of the CNS is the neuron The basic unit of the CNS is the neuron Neurons allow different parts of the body to communicate with each other Neurons allow different parts of the body to communicate with each other The CNS is surrounded by bone-skull and vertebrae. Fluid and tissue also insulate the brain and spinal cord. The CNS is surrounded by bone-skull and vertebrae. Fluid and tissue also insulate the brain and spinal cord.

Peripheral Nervous System Nerves connect the brain and spinal cord to the rest of the body Nerves connect the brain and spinal cord to the rest of the body Cranial nerves in the PNS take impulses to and from the brain Cranial nerves in the PNS take impulses to and from the brain There are two major components of the PNS motor pathways: the somatic and the autonomic There are two major components of the PNS motor pathways: the somatic and the autonomic 1. sensory (afferent) pathways that provide input from the body into the CNS 2. motor (efferent) pathways that carry signals to muscles and glands

Somatic Nervous System Inhibitory signals, cannot be sent through the motor neurons of the somatic system. Inhibitory signals, cannot be sent through the motor neurons of the somatic system. Includes nerves controlling the muscular system and external sensory receptors Includes nerves controlling the muscular system and external sensory receptors External sense organs (including skin) are receptors External sense organs (including skin) are receptors Motor neurons of the somatic system are different from those of the autonomic system. Motor neurons of the somatic system are different from those of the autonomic system.

Autonomic Nervous System -Controls internal organs such as muscles in the heart, smooth muscle in organs, intestines, and bladder -Regulates: Circulation Respiration Digestion Excertion - Requires us to “fight” or take “flight” and allows us to “rest” and “digest” -Helps adapt to changes in environment using two components PNS & SNS

The Sympathetic & Parasympathetic Nervous Systems Active pushing function Located in the sympathetic chain and connects skin, blood vessels, and organs in the body cavity Relaxation function slows the heart rate, increases intestinal and gland activity SNS PNS Both systems innervate the same organs and act in opposition or work in balance with each other directly or indirectly and affect almost every structure in the body

CNS disorders/diseases CNS disorders/diseases are in any component of the brain or the spinal cord. Some common disease/disorders are: Neurogenetic diseases - Huntington’s disease and Muscular dystrophy Neurogenetic diseases - Huntington’s disease and Muscular dystrophy Degenerative diseases of adult life - Parkinson’s and Alzheimer’s disease Degenerative diseases of adult life - Parkinson’s and Alzheimer’s disease Metabolic disease - Stroke Metabolic disease - Stroke Infectious disease - AIDS Infectious disease - AIDS Trauma - Spinal cord and head injury Trauma - Spinal cord and head injury Convulsive disorders - Epilepsy Convulsive disorders - Epilepsy Developmental disorders - Cerebral palsy Developmental disorders - Cerebral palsy Brain tumors Brain tumors

Brain Tumor

Drug effects on the Brain When you consume drugs it makes its way into the blood stream and goes straight to your brain. Whenever you feel pleasure it is your brain secreting dopamine into the amygdala region of your brain. Drugs release an excess amount of dopamine which makes the pleasure more intense. When you continue the use of drugs your brain reduces or stops producing dopamine because the drugs already produce enough. Your brain then relies on the drug and you become addicted. Drugs impair the brain making it hard for the rest of your body to receive messages. Some drugs deteriorate the brain and cause long term effects.

Bibliography By: Jasmin Zamora By: Jasmin Zamora Tyler Williams Tyler Williams Derek Jackson Derek Jackson