Nervous System Flashcards
Central Nervous System (CNS)
Brain and spinal cord
Peripheral Nervous System (PNS)
Nerves and ganglia outside of the CNS; function is to connect CNS to limbs and organs
Neurons
Specialized cells that transmit messages from one part of the body to another
Supporting cells
Neuroglia, or glia (glial cells).
Support, insulate, and protect neurons.
Cell body
Metabolic center of neuron, conspicuous nucleolus
Dendrites
Neuron processes that convey incoming messages toward the cell body
Axon
Neuron processes that generate nerve impulses and conduct them away from the cell body
Myelin Sheath
Whitish, fatty, waxy-looking covering for long nerve fibers.
Protect and insulate fiber and increase the transmission rate of nerve impulses.
Synapse
Functional junction where impulses are generated by axons
Parts of Cerebrum
Cerebral cortex Lobes (frontal, temporal, parietal, occipital) Corpus callosum Left & right hemispheres Sulci & gyri
Parts of Diencephalon
Thalamus
Hyopthalamus
Pituitary gland
Pineal gland
Parts of Brain Stem
Midbrain
Pons
Medulla oblongata
Parts of Cerebellum
Cerebellar cortex
Arbor Vitae
Left, right hemispheres
Major regions of the brain
Cerebrum
Cerebellum
Diencephalon
Brain Stem
Structures that provide protection for the brain
Meninges
Cerebrospinal fluid
Blood-brain barrier
Meninges
Dura mater, arachnoid mater, pia matter
Connective tissue membranes covering and protecting structures of CNS
Cerebrospinal fluid
Watery fluid similar to blood plasma. Forms a cushion around brain and spinal cord, protects nervous tissue from blows and trauma.
Blood-brain barrier
Keeps neurons separated from bloodborne substances, composed of least permeable capillaries in the body
Ventricle
Chamber formed from an enlarged section of central canal. There are 4 in the brain.
Conus medullaris
Cone at the end of the spinal cord, near L1 and L2
Cauda equina
Inferior spinal nerve roots (lumbar, sacral, coccygeal); they must travel inferiorly within the vertebral canal to reach the intervertebral foramina.
Grey matter
Consists of nerve cell bodies, dendrites, unmyelinated axons, glial cells.
White matter funiculi
Specialized tracks in the spinal cord for carrying information quickly to the brain
Dorsal Root Ganglion
Located along dorsal root, contains cell bodies of sensory neurons
How many pairs of spinal nerves are there?
31
How many pairs of cranial nerves are there?
12
Axon terminal
When stimulated by the axon, they release neurotransmitters into the extracellular space of the synaptic cleft.
Central canal
Canal enclosing spinal cord
Protective structures found around the spinal cord
Meninges, dendiculate ligaments, adipose tissue, vertebrae, cerebrospinal fluid
