GL 1b: Basic Concepts of the Nervous System Flashcards
Components of the Peripheral Nervous System (PNS)
- 12 pairs of cranial nerves
- 31 pairs of spinal nerves
- Ganglia
Neuroglia in the CNS:
- Controls ionic environment
- Increases blood supply
Astrocytes
Neuroglia in the CNS: Macrophages of the CNS via phagocytosis
Microglial Cells
Neuroglia in the CNS:
- Lines central cavity of CNS
- Has a semipermeable membrane that allows exchange of fluid (such as CSF)
Ependymal Cells
Neuroglia in the CNS: produces the myeline sheath
Oligodendrocytes
Neuroglia in the PNS: surrounds the cell body
Satellite Cells
Neuroglia in the PNS: produces the myeline sheath
Schwann Cells
Structural class:
- Many processes
- Most abundant
- Major neuron type in the CNS
- Seen in skeletal muscles
Multipolar neurons
Structural class:
- 2 processes
- Seen in special senses
- Seen in the retinal bipolar cells
- Seen in the cells of the sensory cochlear and vestibular ganglia
Bipolar neurons
Structural class:
- 1 process
- Forms central and peripheral processes
- Seen in dorsal root ganglia
- Found mainly in PNS
Unipolar/Pseudounipolar neurons
Difference between nucleus/nuclei and ganglion/ganglia
Nucleus/nuclei - group of neurons in the CNS
Ganglion/ganglia - group of neurons in the PNS
CNS:
- Composed of nerve cell bodies
- Grayish, dull color
Gray Matter
CNS:
- Myelinated fibers/processes
- Glistening white color
- Either ascend or descend bet. the SC and brain
White Matter
Which is located externally? Gray Matter or White Matter?
White Matter
T or F: White matter is external to grey matter surrounding the hollow cavity, INCLUDING the cerebrum and cerebellum.
False. It EXCLUDES the cerebrum and cerebellum
Identification: What structure holds organs in place?
Areolar Tissue
Anatomy of a Nerve: What is covered by the endoneurium?
Axon
Anatomy of a Nerve: What is covered by the perineurium?
Fascicle (group of axons)
Anatomy of a Nerve: What is covered by the epineurium?
The entire nerve (bundles of fiber)
Openings in the skull
Foramina
T or F: First two pairs (olfactory and optic) attach to the forebrain, the rest to the brain stem
True.
T or F: All cranial nerves (except for the glossopharyngeal nerve) are distributed in the head and neck
False. Vagus nerve.
Cranial Nerve:
- Supplies structures in the thorax and abdomen
- Extends out lateral ⅔ of the transverse colon
Vagus Nerve
Name the 12 cranial nerves in order
- Olfactory
- Optic
- Oculomotor
- Trochlear
- Trigeminal
- Abducens
- Facial
- Vestibulocochlear (previously auditory)
- Glossopharyngeal
- Vagus
- Accessory
- Hypoglossal
Name the 3 Primary/Exclusively sensory nerves
Olfactory (I; Smell), Optic (II; Vision), and Vestibulocochlear (VIII; Hearing Equilibrium)
Name the 5 Primary motor nerves
Oculomotor (III), Trochlear (IV), Abducens (VI), Accessory (XI), and Hypoglossal (XII)
*For eyes, neck, and tongue
Name the 4 mixed motor and sensory nerves and their functions
Trigeminal (V):
- S: face
- M: mastication
Facial (VII)
- S: facial muscles
- M: sublingual/submandibular/lacrimal glands; taste (anterior ⅔ of tongue)
Glossopharyngeal (IX)
- S: oral oropharynx and parotid gland
- M: stylopharyngeus muscle
Vagus (X)
- S: head, neck, heart; proximal ⅔ transverse colon)
- M: voice
Nerves involved in the ANS
Oculomotor (III), Facial (VII), Glossopharyngeal (IX), and Vagus (X)
T or F: Each spinal nerve is formed by the combination of a paired bundle of anterior and posterior roots.
True.
Root that contains bundles of efferent (motor) fibers
Anterior Root