Section 9 The Nervous System
Section 9 The Nervous System
Chapter 29 Cells in Nervous System and Their Function ● Neurocyte ● Neuroglia( Glia cell
Chapter 29. Cells in Nervous System and Their Function ⚫ Neurocyte ⚫ Neuroglia (Glia cell)
The Nervous System Components Brain, spinal cord, nerves, sensory receptors Responsible for Sensory perceptions, mental activities stimulating muscle movements, secretions of many glands SubdivⅤ nsions 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 OThe McGrawHll Companies he Pe Centra nervous system Consists of Brain Spinal Brain cord p Inal cor 战绕 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 Dorsal root of spinal nerve Dorsal root ganglion Sensory or afferent Motor Sensory neuron neuron Motor or efferent Spinal Spina Divisions nerve cord Spinal Spinalnerve Somatic nervous cord Sensory receptor ystem Ventral root Skeletal (b) of spinal nerve muscle Autonomic nervous Spinal nerve system(ANS) Spinal cord d 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 Copynight e The McGraw-Hill Companies. he Permission requred for reproduction or display Stimulus Response(output) (input) Cardiac muscle Skeletal smooth muscle muscle and glands PNS Sensory division Somatic Autonomic Sensory 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 Myel Axon sheath Collateral Dendrites. Input hillock formed by axon Schwann cell\ Axons: Output Nissl bodies Nucleus Nucleolus Neuroglia 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 Body Soma Dendrites desynaptIc Terminal Node of handier Axon Myelin ceuS
Part 1 Neuron
1. Structure and function Typical Neuron has 4 Regions Dendrite · Cell body Axon hillock Axon Dendrites Collateral Axon branch Neurofibrils Presynaptic terminals Schwann Each region is specialized Axonal Node of for its particular function wann sheath on 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 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 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
