Chapter 10 Nervous System Microglial cel
Chapter 10 Nervous System
The Nervous System Components Brain, spinal cord, nerves, sensory receptors Responsible for Sensory perceptions, mental activities, stimulating muscle movements, secretions of many glands Subdivisions Central nervous system(CNS) Peripheral nervous system(PNS)
The Nervous System • Components – Brain, spinal cord, nerves, sensory receptors • Responsible for – Sensory perceptions, mental activities, stimulating muscle movements, secretions of many glands • Subdivisions – Central nervous system (CNS) – Peripheral nervous system (PNS)
Central Nervous system Central nervous Consists of system B rain Spinal Brain cord Spinal cord Brain and spinal cord Continuous with each other Cranial Spinal nerves nerves Peripheral nervous system
Central Nervous System • Consists of – Brain – Spinal cord • Brain and spinal cord – Continuous with each other
Peripheral Nervous System ° Two subcategories Sensory or afferent Dorsal root of spinal nerve Dorsal root ganglion Motor Motor or efferent Sensory neuron neuron ·DiⅤ ISIons Spinal Spinal nerve cord Somatic nervous Spir Spinal nerve system cord Sensory recepto Ventral root Skeletal Autonomic nervous (b)of spinal nerve muscle Spinal nerve system(ANS) Spinal cord d Autonomic ganglion >Sympathetic >> Parasympathetic First motor neuron Second motor neuron > Enteric Effector organ(e.g, smooth (c) muscle) Large intestine
Peripheral Nervous System • Two subcategories – Sensory or afferent – Motor or efferent • Divisions – Somatic nervous system – Autonomic nervous system (ANS) »Sympathetic »Parasympathetic »Enteric
Nervous System organization Copyright e The McGraw-Hill Companies. inc Permission requred for reproduction or display Stimulus Response(output) (input) Skeletal Cardiac muscle, muscle smooth muscle and glands PNS Sensory division Somatic Autonomic Sensor ry conducts action nervous nervous receptors, potentials system system nerves, from the Motor division ganglia, periphery conducts action potentials and plexuses to the periphery CNS Brain and Processing and integrating information, spInal cord initiates responses, mental activity
Nervous System Organization
Cells of nervous system Neurons or nerve cells Receive stimuli and Neuron transmit action cell body Presynaptic terminals Dendrites potentials Schwann Node of Axon cell Ranvier Organization Cell body or soma Myelin Axon sheath Collateral Dendrites. Input hillock formed b axon Schwann cell\ Axons: Output Nissl bodies Nucleus Nucleolus euroglla or glial cells Dendritic spIne Golgi apparatus Support and protect Mitochondrion neurons
Cells of Nervous System • Neurons or nerve cells – Receive stimuli and transmit action potentials – Organization • Cell body or soma • Dendrites: Input • Axons: Output • Neuroglia or glial cells – Support and protect neurons
Section 1 General Function of Neuron and neuroglia Ⅰ Neuron Cell bod ISomal Presynaptic Dendrites Terminal Node of ranvier Axon Myelin Nucleus
Section 1 General Function of Neuron and Neuroglia I Neuron
1. Structure and function Typical Neuron has 4 Regions Dendrite Cell Bod Nissl substance Axon hillock A Dendrites Collateral branch Axon Neurofibrils Presynaptic terminals Schwann Each region is specialized AXoN Node of for its particular function forming the myelin sheath on axon Information flows in a single direction
Typical Neuron has 4 Regions • Cell Body • Dendrites • Axon • Presynaptic Terminals Each region is specialized for its particular function Information flows in a single direction 1. Structure and Function
Neuron Cell Body Location o Most are found in the central nervous system o Gray matter- cell bodies and unmylenated fibers o Nuclei- clusters of cell bodies within the white matter of the central nervous system o Ganglia collections of cell bodies outside the central nervous system
Neuron Cell Body Location • Most are found in the central nervous system •Gray matter – cell bodies and unmylenated fibers •Nuclei – clusters of cell bodies within the white matter of the central nervous system • Ganglia – collections of cell bodies outside the central nervous system
Functional classification of Neurons o Sensory(afferent) neurons Carry impulses from the sensory receptors o Cutaneous sense organs e Proprioceptors -detect stretch or tension o Motor(efferent) neurons Carry impulses from the central nervous system
Functional Classification of Neurons • Sensory (afferent) neurons •Carry impulses from the sensory receptors •Cutaneous sense organs •Proprioceptors – detect stretch or tension • Motor (efferent) neurons •Carry impulses from the central nervous system