Nagelhout Chapter 31 Flashcards
2 components of the CNS
Brain and spinal cord
Peripheral nervous system components
Cranial nerves/receptors
Spinal nerves/receptors
Divided into somatic and autonomic nervous systems
The somatic nervous system contains sensory neurons for what parts of the body?
Skin, muscles, and joints
The autonomic nervous system contains what?
Sympathetic
Parasympathetic
Enteric subdivisions
Responsible for involuntary innervation of various organ systems
What 2 primary cell types is the CNS system derived from?
Neurons
Neuroglial (glial) cells
Describe the neuron
Basic functional cell of CNS
Cell body, specialized cytoplasmic process, dendrites, single axon
Diameter 0.2-20µm
Dendrite stimulation produces anterograde impulse conduction toward the neuron cell body and subsequent conduction away from the neuron cell body by way of axon
Classifications of neurons
Unipolar
bipolar
pseudounipolar
multipolar
Where are unipolar neurons found
lower invertebrates
Where are bipolar neurons found?
Retina
ear
olfactory mucosa
Where are pseudounipolar neurons present? What do they assist with?
Dorsal root ganglia
Cranial ganglion cells
Enable sensory impulses to travel from the dendrite directly to the axon without passing through the cell body.
What are the components of the multipolar neurons?
Multiple dendritic processes but only one axon
Constitute the majority of the CNS neurons
What composes gray matter?
Neuron cell bodies in CNS
What composes white matter?
Myelinated axons
Motor neuron function
Multipolar
Innervate/control effector tissues suhc as muscles and glands
Sensory neuron function
pseudounipolar
Receive exteroceptive, interoceptive, proprioceptive input
Interneuron function
Pseudounipolar
Connect adjacent neurons
Four types of glial cells found within the CNS
Astrocytes
Oligodendrocytes
Microglial
Ependymal
Role of neuroglia (glial) cells
Maintenance of proper ionic environment
Modulation of nerve cell electrical conduction
Control of neurotransmitter reuptake
Repair after neuronal injury
What is the predominant glial cell?
Astrocytes
Astrocytes provide ___________ neuronal support, group and pair _________ and nerve terminals, regulate the ____________ environment, and are active in _________ after neuronal injury.
Astrocytes provide
structural neuronal support, group and pair neurons and nerve
terminals, regulate the metabolic environment, and are active in
repair after neuronal injury.
What are the two distinct types of astrocytes?
Fibrous astrocytes: found in white matter
Protoplasmic astrocytes: concentrated in gray matter
