Nerves 1 Flashcards
What are the three functions of the Nervous system?
Sensory (receives stimuli)
Integrative (interprets and processes stimuli)
Effector (produces outgoing signal to initiate a response)
What is the CNS?
Central Nervous System
Brain and Spinal Cord
What is the PNS?
Peripheral Nervous System
Any neural tissue outside CNS
Describe the CNS
Contained within skull and vertebrae
Integrative in function (processes and understands sensory information to translate it into a response)
Describe the PNS
Outside of skull and vertebrae
Peripheral Nerves
Peripheral Ganglia
Sensory organs of vision, hearing, etc.
What are peripheral nerves?
Cranial and Spinal nerves
What are peripheral ganglia?
Sensory ganglia
Autonomic nervous system ganglia
Afferent division of Peripheral Nerves
Bring sensory information in from receptors
Efferent division of Peripheral nerves
Carries motor commands to effectors
Define Nerve cells
Electrically active cells that process and conduct information in the form of electrical signals
Define Neuroglia
Support cells
What neuroglia are in the PNS?
Satellite cells
Schwann Cells
What neuroglia are in the CNS?
Oligodendrocytes
Astrocytes
Microglia
Ependymal cells
What do oligodendrocytes do?
Myelinate axons
What do astrocytes do?
General support cells
What do microglia do?
clean up damage
What do schwann cells?
myelinate axons
What fibers transmit information in the PNS?
Nerves
What fibers transmit information in the CNS?
White matter, fiber tract, column
What nerve cell bodies process information in PNS?
Ganglia
What nerve cell bodies process information in CNS?
Grey matter, nucleus, cortex
____ gray horns contain somatic and visceral sensory nuclei
Posterior
____ gray horns deal with somatic motor control
Anterior
____ gray horns contain visceral motor neurons
Lateral
Size of grey matter (number of nerve cells) is related to
The size of body innervated
Ascending white matter tracts
relay information from spinal cord to the brain
Descending white matter tracts
carry information from brain to spinal cord
The adult spinal cord
8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccyx
_____ root of spinal nerve is afferent
Dorsal
___ root of spinal nerve is efferent
Ventral
Define dermatomes
Region of the skin monitored by the sensory afferents of a single spinal segment
Define telencephalon
cerebrum
Define diencephalon
thalamus and hypothalamus
Define mesencephalon
midbrain
Define metenchephalon
pons and cerebellum
Define myelencephalon
medulla oblongata
Where is the highest level of processing located?
Cerebral Hemispheres
The basal nuclei of cerebral hemispheres
dictate motor control
The thalamus
Relays sensory information to appropriate processing center
The hypothalamus
Is involved with ANS and endocrine control
The cortex of cerebellum
Coordinates motor control
Define projection fibers
Ascending and descending tracts of the spinal cord, brainstem, and brain (connect up to down)
Define association fibers
Connect between areas on the same side of the CNS
Define commissural fibers
Connect between areas on opposite sides of CNS (connect right to left)
Brain and spinal cord tissue develop from
Cells in the walls of the developing hollow neural tube
Ventricles of brain and spinal canal of spinal cord develop from
Hollow center of neural tube
What support mechanisms are there of the CNS?
Skull Vertebrae Ligaments Muscles Meninges CSF Blood Brain barrier
Define Meninges
Specialized connective tissue layers (Dura, arachnoid, pia matter)
Provide physical stability and shock absorption
Support blood vessels entering and exiting CNS tissue
Cerebrospinal fluid is
Produced in ventricles
Fills subarachnoid space
How is CSF produced
Diffused out of capillaries into choroid plexus into ventricles
Although CSF comes from blood and returns to blood
IT IS NOT BLOOD
What does CSF do?
Transports nutrients, chemical messengers, and waste products
Provides cushioning and buoyancy
Blockage of CSF circulation
Causes pressure in ventricles (hydrocephalus)
