Module 5 (NERVOUS TISSUE) Flashcards
Most complex system in the body histologically and physiologically.
NERVOUS TISSUE
Formed by a network of many billion nerve cells (neurons), assisted by many more glial cells.
NERVOUS TISSUE
DIVISION OF NERVOUS SYSTEM
CENTRAL NERVOUS SYSTEM
PERIPHERAL NERVOUS SYSTEM
consisting of the brain and spinal cord
CENTRAL NERVOUS SYSTEM
composed of cranial, spinal, and peripheral nerves conducting impulses to and from the CNS (motor and sensory nerves respectively) ang ganglia which are small groups of nerve cells outside the CNS.
PERIPHERAL NERVOUS SYSTEM
aka nerve cells
NEURONS
Functional unit in both CNS and PNS
NEURONS
Four parts of Neurons
Cell body / perikaryon
Dendrites
Axon
Terminal Arborization
synthetic or trophic center for the entire nerve cell and is receptive to stimuli
Cell body / perikaryon
many elongated processes specialized to receive stimuli from the environment, sensory epithelial cells, or other neurons
Dendrites
a single process specialized in generating and conducting nerve impulses to other cells (nerve, muscle and gland cells). It may also receive information that mainly modifies the transmission of action potentials to those neurons
Axon
CLASSIFICATION OF NEURONS
MULTIPOLAR NEURONS
BIPOLAR NEURONS
UNIPOLAR or PSEUDOUNIPOLAR NEURONS
branched distal portion of the axon. Each branch terminatees on the next cell
Terminal Arborization
which have one axon and two or many dendrites
MULTIPOLAR NEURONS
one dendrite and one axon
BIPOLAR NEURONS
which have a single process that bifurcates close to the perikaryon, with the longer branch extending to a peripheral ending and the other toward CNS.
UNIPOLAR or PSEUDOUNIPOLAR NEURONS
most neurons are ?
MULTIPOLAR
neurons are found in retina, olfactory mucosa, cochlear /9inner ear) and vestibular ganglia, which they serve as senses of sight, smell, and balance respectively.
BIPOLAR neurons
neurons are found in the spina ganglia and most in cranial ganglia.
PSEUDOUNIPOLAR neurons
Types of Glial Cells
Oligodendrocyte
Neurolemmocyte
Astrocyte
Ependymal Cells
Microglia
Oligodendrocyte LOCATION and FUNCTION
CNS
Myelin production, electric insulation
Neurolemmocyte LOCATION and FUNCTION
Peripheral nerves
Myelin production, electric insulation
Astrocyte LOCATION and FUNCTION
CNS
Structural support, repair processes ; BBB, metabolic exchanges
Microglia LOCATION and FUNCTION
CNS
Immune-related activity
Ependymal cells LOCATION and FUNCTION
CNS
Lining cavities of CNS
Principal structures of CNS
CEREBRUM
CEREBELLUM
SPINAL CORD
IT has virtually no connective tissue and is therefore a relatively soft, gel-like organ
CENTRAL NERVOUS SYSTEM
