Peripheral Nervous System Two subcategories Dorsal root of spinal nerve Dorsal root ganglion Sensory or afferent sEnsory neuron Motor neuron Motor or efferent Spinal Spinal nerve ·DiⅤ ISIons ord Spinal Spinalnerve Somatic nervous cord Sensory receptor system Ventral root Skeletal (b) of spinal nerve muscle Autonomic nervous Spinal nerve system(ANS) Spinal cord Autonomic ganglion >Sympathetic First motor neuron >> Parasympathetic Second motor neuron Effector organ(e.g, smooth > Enteric (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 pynght e The McGraw-Hill Companies. inc Permission required for reproduction or display Stimulus Response(output) (input) Skeletal Cardiac muscle, muscle smooth muscle, and glands PNS Sensory division Somatic Autonomic Sensory conducts action nervous nervous receptors, potentials system system nerves from the t 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
Part 1 Neuron Cell bod [) Presynaptic Dendrites Terminal Node of ranvier Axon Myelin 券紫 Nucleus
Part 1 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