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ight © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Fundamentals of Anatomy & Physiology SIXTH EDITION Chapter 12, part 1 Neural tissue
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings
Fundamentals of
Anatomy & PhysiologySIXTH EDITION
Chapter 12, part 1
Neural tissue
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings
Learning Objectives
• Describe the two major divisions of the nervous system and their characteristics.
• Identify the structures/functions of a typical neuron.
• Describe the location and function of neuroglia.
• Explain how resting potential is created and maintained.
• Describe the events in the generation and propagation of an action potential.
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings
Learning Objectives
• Define the structure/function of a synapse.
• List the major types of neurotransmitters and neuromodulators.
• Explain the processing of information in neural tissue.
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings
SECTION 12-1 An Overview of the Nervous System
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nervous system overview
• Nervous system
• Provides swift, brief responses to stimuli
• Endocrine system
• Adjusts metabolic operations and directs long-term changes
• Nervous system includes
• All the neural tissue of the body
• Basic unit = neuron
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Divisions of the Nervous system
• CNS (Central Nervous system)
• Brain and spinal cord
• PNS (Peripheral Nervous system)
• Neural tissue outside CNS
• Afferent division brings sensory information from receptors
• Efferent division carries motor commands to effectors
• Efferent division includes somatic nervous system and autonomic nervous system
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Figure 12.1 Functional Overview of the Nervous System
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SECTION 12-2 Neurons
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• Perikaryon
• Neurofilaments, neurotubules, neurofibrils
• Axon hillock
• Soma
• Axon
• Collaterals with telodendria
Neuron structure
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Figure 12.2 The Anatomy of a Multipolar Neuron
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• Site of intercellular communication
• Neurotransmitters released from synaptic knob of presynaptic neuron
Synapse
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Figure 12.3 The Structure of a Typical Synpase
Figure 12.3
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• Anatomical
• Anaxonic
• Unipolar
• Bipolar
• Multipolar
Neuron classification
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Figure 12.4 A Structural Classification of Neurons
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• Sensory neurons
• deliver information from exteroceptors, interoceptors, or proprioceptors
• Motor neurons
• Form the efferent division of the PNS
• Interneurons (association neurons)
• Located entirely within the CNS
• Distribute sensory input and coordinate motor output
Functional
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Figure 12.5 A Functional Classification of Neurons
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SECTION 12-3 Neuroglia
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• Four types of neuroglia in the CNS
• Ependymal cells
• Related to cerebrospinal fluid
• Astrocytes
• Largest and most numerous
• Oligodendrocytes
• Myelination of CNS axons
• Microglia
• Phagocytic cells
Neuroglia of the Central Nervous System
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Figure 12.6 An Introduction to Neuroglia
Figure 12.6
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Figure 12.7 Neuroglia in the CNS
Figure 12.7a
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Figure 12.7 Neuroglia in the CNS
Figure 12.7b
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• Two types of neuroglia in the PNS
• Satellite cells
• Surround neuron cell bodies within ganglia
• Schwann cells
• Ensheath axons in the PNS
Neuroglia of the Peripheral Nervous System
Animation: Nervous system anatomy reviewPLAY
