Dr. S. M. Robichaux
2f, 30, 63, 71-c, 71-g, 71-m, 72-a, 72-m, 72-t, 74-b, 74-g, 81-a, 86-p,
92-b, 92-c or 92-d, 148
A. Nervous Tissue:
This tissue is composed of neurons (nerve cells), which have
numerous protoplasmic extensions (axons and dendrites) and is supported by special
connective tissue cells (neuroglia).
Neurons are grouped as circuits to provide rapid
communication between groups of serially disposed cells.
This permits rapid
transmission of information over long distances. The functions of nervous tissue are to
receive stimuli, transform the stimuli into nervous excitations, transmit and evoke
1. Organization of nervous tissue:
Central Nervous System (CNS)
: brain, brain stem and spinal cord
Peripheral Nervous System (PNS)
: spinal nerves and ganglion, cranial
nerves and ganglion.
: the anatomical and physiological unit of nervous tissue and
consists of the cell body and its fibers.
(1) Neuronal classifications: page 321 in text
: a neuron with a single axon and a single
dendrite opposite a spindle shaped cell body; associated with the receptors for the
special senses (taste, smell, hearing, sight and equilibrium); located in the retina
of the eye, olfactory epithelium of the nasal cavity and cochlea of the inner ear.
: a single process arises from the neural
cell body; this process bifurates to form one branch that functions as the axon and the
other to function as the dendrite; located in craniospinal ganglia; sensory.
: neurons which contain a single axon and
numerous dendrites; include the motor neurons and interneurons.
: receive sensory stimuli from receptors
to the central nervous system.
: convey impulses from the CNS or from
ganglia to effector cells (muscles and glands)
: form a communicating and integrating
network between the sensory and motor neurons.
Golgi type I neurons
: cells having a well-developed
dendritic tree and a long axon; includes the pyramidal and Purkinje cells.
Golge type II neurons
: cells having many short
dendrites and one short axon; includes interneurons.