Anatomy & Physiology Essentials - Chapter 7 - PDF

Presentations for PowerPoint Anatomy & Physiology Essentials 7 The Nervous System 7.1 Anatomy of the Nervous System Section 7.1 Objectives Explain the general organization of the human nervous system. Describe the types of tissues present in the nervous system and identify the gen...

Presentations for PowerPoint Anatomy & Physiology Essentials 7 The Nervous System 7.1 Anatomy of the Nervous System Section 7.1 Objectives Explain the general organization of the human nervous system. Describe the types of tissues present in the nervous system and identify the general role of each. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Structural Divisions Central nervous system (CNS) Includes brain and spinal cord Directs activity of entire nervous system Peripheral nervous system (PNS) Includes spinal nerves, cranial nerves, and sensory receptors Transmits information and responds to stimuli Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Functional Divisions Afferent nerves Somatic sensory fibers Visceral sensory fibers Efferent nerves Somatic nervous system Autonomic nervous system Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Nervous System Organization Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Neurons © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Types of Neurons © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Neuron Structures © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. 7.2 Impulse Transmission Section 7.2 Objectives Explain what action potentials are and how they are generated. Explain the factors that influence the speed of neural impulse transmission. Describe the role of neurotransmitters in transmitting impulses across synapses. Describe the two types of reflexes and explain how they work. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Action Potentials Neuron states Polarized Depolarized Refractory period Repolarized Sodium-potassium pump Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. 7 Main Neurotransmitters Acetylcholine Dopamine Gaba (Gamma-aminobutyric acid) Glutamate Histamine Norepinephrine Serotonin Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Neurotransmitters Excitatory or inhibitory effect on receiving cell © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Reflexes Somatic reflexes Stimulation of skeletal muscles Example: removing hand from something hot Autonomic reflexes Regulate cardiac muscle and smooth muscle Examples: digestion, elimination, sweating, and blood pressure Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Reflex Example © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. 7.3 Central Nervous System Section 7.3 Objectives Identify and describe the major parts of the brain, including the cerebrum, diencephalon, brainstem, cerebellum, meninges, and blood-brain barrier. Explain the structure and functions of the spinal cord. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Hemispheres of the Cerebrum Alex Mit/Shutterstock.com Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Lobes of the Cerebrum © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Functional Regions of the Brain © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Motor and Somatic Sensory Cortexes © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Diencephalon Interbrain Enclosed by cerebral hemispheres Important structures Thalamus Hypothalamus Epithalamus Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Brainstem Reticular activating system Regulates states Damage may result in coma © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Cerebellum Coordinates body movements Receives input from eyes, ears, and sensory receptors Monitors body segment positions and movements Sends out signals to make adjustments Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Meninges Protective membranes © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Blood-Brain Barrier Blocks surges in concentrations of hormones, ions, and some nutrients Allows water, glucose, and essential amino acids to pass Allows blood-borne alcohol, nicotine, fats, respiratory gases, and anesthetics Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Spinal Cord Extends from brainstem to beginning of lumbar region © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.  Peripheral Nervous System 7.4 Peripheral Nervous System Section 7.4 Objectives Describe the basic structure of a nerve. Identify the twelve cranial nerves and the purpose of each. Explain the organization of the spinal nerves, the dorsal and ventral rami, and the plexuses. Differentiate between the functions of the sympathetic and parasympathetic nerves within the autonomic nervous system. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Nerve Structure © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Cranial Nerves © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Spinal Nerves © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Spinal Nerve Plexuses Cervical Brachial Lumbar Sacral © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Lumbar and Sacral Plexuses © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Autonomic Nervous System © Body Scientific International Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Sympathetic Nerves Fight-or-flight response Acetylcholine secreted to stimulate paravertebral ganglia Norepinephrine released by postganglionic neurons Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Parasympathetic Nerves Functions Control circulatory, respiratory, and digestive systems Calm system after fight-or-flight response Activation of neurons releases acetylcholine Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. 7.5 Development of the Nervous System Section 7.5 Objectives Explain the role of neural progenitor cells in the development of the nervous system. Describe the major developmental changes that the brain undergoes during childhood and adolescence. Describe the functional changes to the aging brain in late adulthood. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Embryonic and Fetal Periods Neural progenitor cells (neural stem cells) Produce the different cells that make up CNS Neurons organize into primitive neural networks At week 7, neurons begin to form From week 9 through birth, gyri and sulci form First fissure separates two cerebral hemispheres Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Infancy, Childhood, and Adolescence Structural changes in brain and spinal cord Dramatic increase in myelination of neurons Functional organization Romrodphoto/Shutterstock.com Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Adulthood Brain reaches full size at about age 25 From then on, brain and spinal cord lose volume and weight Brain function tends to decline Short-term memory, verbal abilities, intellectual capacity Conduction of impulses by peripheral nerves slows Regular exercises postpones effects of aging Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. 7.6 Nervous System Injuries and Disorders Section 7.6 Objectives Describe the symptoms and recovery strategies for someone who has suffered a traumatic brain or spinal cord injury. Describe common diseases and disorders of the nervous system. Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Traumatic Brain Injury (TBI) Mild May lose consciousness Symptoms Moderate to severe More serious symptoms Require immediate medical care Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Current Treatment and Prevention of TBI Follow-up care: individualized rehabilitation programs Prognosis for TBI varies greatly Research to develop strategies and interventions Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Cerebral Palsy (CP) Group of nervous system disorders Caused by congenital defects or in early infancy Varying degrees of motor function impairment Can include hearing, vision, and cognitive impairment Spastic CP is most common No cure Surgical intervention can improve some symptoms Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Spinal Cord Injury Fracture or displacement of the vertebrae Complete severing of spinal cord C1-C3—usually fatal C1-C4—quadriplegia C5-C7—complete paralysis of lower extremities; partial loss of function in trunk and upper extremities T1-L5—paraplegia Medical emergency—immobilized before movement Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Meningitis Inflammation of meninges surrounding brain and spinal cord Swelling produces symptoms Caused by viral, bacterial, and fungal infections Viral meningitis Bacterial meningitis Cephalosporins – (Cefotaxime, Ceftriaxone) - Penicillin, Ampicillin Seek immediate medical attention Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Multiple Sclerosis Autoimmune disease of unknown cause Inflammation destroys myelin sheath Can occur at any age Occurs with greater frequency in women Cause is unknown Symptoms vary widely No known cure Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Epilepsy Group of brain disorders characterized by repeated seizures Symptoms depend on type of epilepsy and area of brain affected Caused by disease or injury that affects brain Seizures are relatively consistent in given individual Controlled with medication Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Epilepsy Medication - GABA Analogs (gabapentin, pregabalin) - Carboxamides (Carbamazepine, Rufinamide) - Calcium Channel modulators (Levetiracetam) - AMPA Receptor Antagonist (Perampanel) Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Parkinson’s Disease Common among elderly Tremors, difficulty initiating movements, and deficits in coordination Men and women equally affected Slow, progressive destruction of brain cells that produce dopamine Motor dysfunction on one or both sides of body Impairment of autonomic and cognitive functions No cure Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Huntington’s Disease Genetic mutation passed down through families Causes degeneration of neurons in brain Age of onset and rate of progression vary Neuromuscular disorders Intellectual impairments Psychiatric disorder Medications and genetic engineering Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Dementia Loss of function in two or more areas of cognition Usually occurs after age 60 Can be caused by disruption in blood supply to brain Most common cause is Alzheimer’s disease Progressive loss of brain function No known cause Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Alzheimer’s Disease (AD) Early onset AD appears before age 60 Worsens quickly Believed to involve genetic predisposition Late onset AD is the most common form Early symptoms Worsening symptoms Advanced symptoms Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Medical Terminology Practice (1 of 2) Identify the word parts that make up the following terms. Then use your knowledge of medical word parts to define the terms. Congenital Word parts: con- = together, -genit/o = reproduction, -al = pertaining to Meaning: pertaining to reproduction Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Medical Terminology Practice (2 of 2) Epineurium Word parts: epi- = upon, -neur/o = nerve, -ium = structure Meaning: outer covering of a nerve Myelophthisis Word parts: myel/o = spinal cord, -phthisis = atrophy Meaning: atrophy of the spinal cord Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Review (1 of 5) What two structures make up the central nervous system? Brain and spinal cord Which nervous system stimulates the skeletal muscles? Somatic What are the two specialized types of cells that exist within the nervous system? Neurons and neuroglia Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Review (2 of 5) What is the refractory period in a nerve fiber? The time between the completion of the action potential and repolarization What are the two types of reflexes, and which type regulates the cardiac muscle of the heart? Somatic and autonomic; autonomic regulates the cardiac muscle Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Review (3 of 5) What are the four major anatomic regions of the brain? Cerebrum, diencephalon, brainstem, and cerebellum Name the lobes of the brain. Frontal, parietal, occipital, and temporal What are the four plexuses in the body? Cervical, brachial, lumbar, and sacral Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Review (4 of 5) What system controls all of the automatic, everyday functions of the circulatory, respiratory, and digestive systems? Parasympathetic nervous system What brain function tends to be the first to diminish? Short-term memory What determines the extent of a spinal cord injury if the spinal cord is severed? The level at which the cord is severed Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Review (5 of 5) What are the two types of meningitis, and which one is potentially life threatening? Viral and bacterial; bacterial is much more serious Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website.