Chapter 10.4
neurons are classified into three major groups based on what?
structural differences and functional differences
how are the cells of nervous tissue intimately related?
they extend from the same neural stem cells and remain associated throughout their existence
most sensory neurons have what type of cell structure?
unipolar
the cell bodies of this neuron can be found in ganglia
unipolar
the cell bodies of some interneurons aggregate in specialized masses of nervous tissue called___________?
nuclei
resemble astrocytes, but are smaller and have fewer processes
oligodendrocytes
functional characteristics of an interneuron
relays information between neurons in the brain and spinal chord
at their distal ends, the dendrites of these neurons act as receptors, detecting changes in the outside world
sensory neurons
neurons are functionally classified as ________________?
sensory neurons, interneurons, and motor neurons
the 10 functions of neuroglia
1. fill spaces 2. support neurons 3. hold nervous tissue together 4. help metabolize glucose 5. help regulate potassium ion concentration 6. produce myelin 7. carry on phagocytosis 8. rid synapses of excess ions and neurotransmitters 9. nourish neurons 10. stimulate synapse formation
neuroglia that aids the metabolism of certain substances
astrocytes
neuroglia that provide support and hold structures together with abundant cellular processes
astrocytes
play an important role in the blood brain barrier
astrocytes
star-shaped cells found between blood vessels
astrocytes
the four types of CNS neuroglia
astrocytes, oligodendrocytes, microglia, and ependyma
types of neuroglia in the CNS
astrocytes, oligodendrocytes, microglia, and ependymal cells
these neurons are found in special parts of the eyes, nose, and ears
bipolar neurons
structural characteristic of a bipolar neuron
cell body with a process arising from each end; one axon and the other a dendrite
structural characteristic of a unipolar neuron
cell body with a single process that divides into two branches and functions as an axon
structural characteristic of a multipolar neuron
cell body with many processes, one of which is an axon, the rest dendrites
functional characteristics of a motor neuron
conducts impulses from the brain or spinal chord out to effectors-muscles or glands
functional characteristics of a sensory neuron
conducts impulses from the receptors in peripheral body parts into the brain or spinal chord
location of a unipolar neuron
found in the ganglia
location of a bipolar neuron
in specialized parts of the eyes, nose, and ears
location of a multipolar neuron
most common type of neuron in the brain and the spinal chord; but is also found in the ganglia of the autonomic nervous system
structural characteristic of a sensory neuron
most unipolar, but some are bipolar and multipolar
structural characteristic of a motor neuron
multipolar
structural characteristic of an interneuron
multipolar
most neurons that lie within the brain or spinal chord are this type
multipolar neuron
neurons are structurally classified as ______________?
multipolar, bipolar, and unipolar