* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Functional Classification of the Peripheral Nervous System
Subventricular zone wikipedia , lookup
Neuromuscular junction wikipedia , lookup
Neural coding wikipedia , lookup
Multielectrode array wikipedia , lookup
Psychoneuroimmunology wikipedia , lookup
Electrophysiology wikipedia , lookup
Caridoid escape reaction wikipedia , lookup
Endocannabinoid system wikipedia , lookup
Single-unit recording wikipedia , lookup
Neurotransmitter wikipedia , lookup
Biological neuron model wikipedia , lookup
Central pattern generator wikipedia , lookup
Premovement neuronal activity wikipedia , lookup
Neural engineering wikipedia , lookup
Molecular neuroscience wikipedia , lookup
Clinical neurochemistry wikipedia , lookup
Optogenetics wikipedia , lookup
Node of Ranvier wikipedia , lookup
Axon guidance wikipedia , lookup
Synaptic gating wikipedia , lookup
Synaptogenesis wikipedia , lookup
Development of the nervous system wikipedia , lookup
Feature detection (nervous system) wikipedia , lookup
Nervous system network models wikipedia , lookup
Microneurography wikipedia , lookup
Neuropsychopharmacology wikipedia , lookup
Channelrhodopsin wikipedia , lookup
Circumventricular organs wikipedia , lookup
Stimulus (physiology) wikipedia , lookup
Essentials of Human Anatomy & Physiology The Nervous System Chapter 7 Nervous System Functions 1. Sensory input – gathered information Allows you to monitor changes occurring in & outside of the body (changes = stimuli) 2. Integration Process and interpret the sensory input and decide if action is needed 3. Motor output A response to integrated stimuli activates muscles or glands Structural Classification of the Nervous System Central Nervous System (CNS) Brain Spinal cord Peripheral Nervous System (PNS) Nerves that extend from the brain and spinal cord Functional Classification of the Peripheral Nervous System Sensory (afferent) division Nerve fibers that carry information to the central nervous system Functional Classification of the Peripheral Nervous System Motor (efferent) division Nerve fibers that carry impulses away from the central nervous system Functional Classification of the Peripheral Nervous System Motor (efferent) division Two subdivisions Somatic nervous system = Voluntary Autonomic nervous system = Involuntary Sympathetic Parasympathetic Organization of the Nervous System Nervous Tissue: Support Cells Supporting Cells in the CNS Lumped together as neuroglia (AKAglia or glial cells) “Nerve glue” Includes many types of cells that support, insulate, & protect the delicate neurons Each type has specific functions Nervous Tissue: Neurons Neurons = Nerve cells Cells specialized to transmit messages Nerve impulses Major regions of Neurons Cell body – Contains the nucleus and is the metabolic center of the cell Processes – Fibers that extend from the cell body (dendrites and axons) Neuron Anatomy Cell body Nucleus Metabolic Center Neuron Anatomy Extensions outside the cell body Dendrites – Conduct impulses toward the cell body Axons – Conduct impulses Away from the cell body Axons and Nerve Impulses Axons end in axonal terminals Axon terminals contain vesicles that contain neurotransmitters Axon terminals are separated from the next neuron by a gap Synaptic cleft – just the space between adjacent neurons Synapse – junction between neurons; including the membranes of both neurons & the space between them Nerve Fiber Coverings Myelin Covers nerve fibers Whitish, fatty material Waxy appearance Protects & insulates the fibers Increases the transmission rate of nerve impulses Schwann cells – produce myelin sheaths in jelly-roll like fashion Nodes of Ranvier – gaps in the myelin sheath along the axon Application of Neurons • Multiple sclerosis (MS) • Chronic, potentially debilitating disease that affects the central nervous system, which is made up of the brain and spinal cord. • Myelin sheath is destroyed- It hardens to a tissue called the scleroses • Transmitted nerve impulses are short-circuited • Affected person loses control of his/her muscles and becomes increasingly more disabled • Autoimmune disease • Protein component of the sheath is attacked • No cure • Interferon injections • • website Hormone like substance released by some immune cells- provides relief Multiple Sclerosis Neuron Cell Body Location Most neurons are found in the central nervous system White matter- dense collections of myelinated fibers Gray matter – unmyelinated fibers & cell bodies Nuclei – clusters of cell bodies within the white matter of the central nervous system Ganglia – collections of cell bodies outside the central nervous system (PNS) Functional Classification of Neurons Sensory (afferent) neurons Carry impulses from the sensory receptors to the CNS Cutaneous sense organs (Vision, hearing, equilibrium, taste & smell) Proprioceptors – detect stretch or tension in skeletal muscles, tendons and joints Pain receptors Functional Classification of Neurons Motor (efferent) neurons Carry impulses from the central nervous system to the viscera and/or muscles and glands Interneurons (association neurons) • Connect sensory and motor neurons in neural pathways Neuron Classification