Chapter 35
The Nervous System
By Boundless
Neurons and glia coordinate actions and transmit signals in the CNS and PNS.
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Four major types of neurons transmit signals through the body via specialized structures such as dendrites, axons, and synapses.
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The seven types of glia have specific functions that play a role in supporting neuron function.
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The resting potential of a neuron is controlled by the difference in total charge between the inside and outside of the cell.
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Signals are transmitted from neuron to neuron via an action potential, when the axon membrane rapidly depolarizes and repolarizes.
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Synaptic transmission is a chemical event which is involved in the transmission of the impulse via release, diffusion, receptor binding of neurotransmitter molecules and unidirectional communication between neurons.
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Signal summation occurs when impulses add together to reach the threshold of excitation to fire a neuron.
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Synapses experience plasticity by strengthening or weakening over time.
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The cerebral cortex of the brain is divided into four lobes responsible for distinct functions: frontal, parietal, temporal, and occipital.
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Regions of the brain other than the cerebral cortex include those involved in sleep, memory, attention, motor coordination, and motivation.
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The spinal cord is a bundle of nerves that is connected to the brain and relays information from the brain to the body and vice versa.
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The autonomic nervous system, the relay between the CNS and internal organs, is divided into the sympathetic and parasympathetic systems.
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The sensory-somatic nervous system transmits sensory information from the body to the brain and motor movements from the brain to the body.
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Alzheimer's disease and Parkinson's disease are both neurodegenerative disorders characterized by loss of nervous system functioning.
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Autism and ADHD are neurodevelopmental disorders that arise when nervous system development is disrupted.
Schizophrenia and depression are just two examples of mental illnesses caused by a disorder of the nervous system.
Epilepsy and stroke are examples of neurological disorders that arise from malfunctions in the nervous system.