Intro To Neuroanatomy Flashcards
(38 cards)
Nervous system has three major functions:
•
•
•
Nervous system has three major functions:
• Sensory - monitors internal & external environment through presence of receptors
• Integration - interpretation of sensory information (information processing); complex (higher order) functions
• Motor - response to information processed through stimulation of effectors
• muscle contraction
“ glandular secretion
Nervous system has three major functions:
• ——— - monitors internal & external environment through presence of receptors
• ——— - interpretation of sensory information (information processing); complex (higher order) functions
• ——— - response to information processed through stimulation of effectors
• muscle contraction
“ glandular secretion
Nervous system has three major functions:
• Sensory - monitors internal & external environment through presence of receptors
• Integration - interpretation of sensory information (information processing); complex (higher order) functions
• Motor - response to information processed through stimulation of effectors
• muscle contraction
“ glandular secretion
General Organization of the nervous system
• Two Anatomical classifications and their divisions
General Organization of the nervous system
• Two Anatomical Divisions
• Central nervous system (CNS)
• Brain
• Spinal cord
• Peripheral nervous system (PNS)
• All the neural tissue outside CNS
• Afferent division (sensory input)
• Efferent division (motor output)
-somatic nervous system
-autonomic nervous system
Types of neural cells in the nervous system
Neurons
Neuroglia
List the CNS and PNS Neuroglia cells
CNS:
-astrocytes
- oligodendrocytes
-microglia
-ependymal cells
PNS:
-Schwann cells (neurolemmocytes)
Satellite cells
Functions of Astrocytes
Astrocytes
• create supportive framework for neurons
• create “blood-brain barrier”
• monitor & regulate interstitial fluid surrounding neurons
• secrete chemicals for embryological neuron formation
• stimulate the formation of scar tissue secondary to CNS injury
Function of oligodendrocytes
Oligodendrocytes
• create myelin sheath around axons of neurons in the CNS.
Myelinated axons transmit impulses faster than unmyelinated axons
Function of microglia
Brain macrophages
Phagocytize cellular wastes and pathogens
Function of ependymal cells
Line ventricles of brain and central canal of spinal cord
Produce, monitor and help circulate CSF
Function of Schwann cells
Schwann cells
• surround all axons of neurons in the
PNS creating a neurilemma around them. Neurilemma allows for potential regeneration of damaged axons
• creates myelin sheath around most axons of PNS
Function of Satellite cells
Satellite cells
• support groups of cell bodies of neurons within ganglia of the PNS
•Most axons of the nervous system are surrounded by a ——— (myelinated axons)
•The presence of ——— speeds up the transmission of action potential along the axon
Myelin will get laid down in segments (internodes) along the axon, leaving unmyelinated gaps known as “———”
•Regions of the nervous system containing groupings of myelinated axons make up the “———”
•”———” is mainly comprised of groups of neuron cell bodies, dendrites & synapses (connections hetween neurons)
•Most axons of the nervous system are surrounded by a myelin sheath (myelinated axons)
•The presence of myelin speeds up the transmission of action potential along the axon
Myelin will get laid down in segments (internodes) along the axon, leaving unmyelinated gaps known as “nodes of Ranvier”
•Regions of the nervous system containing groupings of myelinated axons make up the “white matter”
•”gray matter” is mainly comprised of groups of neuron cell bodies, dendrites & synapses (connections hetween neurons)
——— perform all of the communication, information processing, and control functions of the nervous system. ——— outnumber neurons and have functions essential to preserving the physical and biochemical structure of neural tissue and the survival of neurons
Neurons perform all of the communication, information processing, and control functions of the nervous system. Neuroglia À outnumber neurons and have functions essential to preserving the physical and biochemical structure of neural tissue and the survival of neurons
Structural classification based on number of processes coming off of the cell body:
Anaxonic neuron
Bipolar neuron
Pseudopolar neuron
Multipolar neuron
Anatomical organization of neurons
Neurons of the nervous system tend to group together into organized bundles
The axons of neurons are bundled together to form ——— in the
PNS & ——— in the CNS. Most axons are myelinated so these structures will be part of “———”
The cell bodies of neurons are clustered together into ——— in the PNS & ——— in the CNS. These are unmyelinated structures and will be part of “———”
Anatomical organization of neurons
Neurons of the nervous system tend to group together into organized bundles
The axons of neurons are bundled together to form nerves in the
PNS & tracts/pathways in the CNS. Most axons are myelinated so these structures will be part of “white matter”
The cell bodies of neurons are clustered together into ganglia in the PNS & nuclei/centers in the CNS. These are unmyelinated structures and will be part of “gray matter”
———Gray matter on the surface of the brain
Neural Cortex
———Collections of neuron cell bodies in the CNS; each center has specific processing functions
Centers
———- The most complex centers in the brain
High centers
———Several tracts that form an anatomically distinct mass
Tracts
The brain and spinal cord are invested by three concentric membranes
1.
2.
3.
The brain and spinal cord are invested by three concentric membranes
1. The outermost layer is the dural matter.
2. The middle layer is the archnoid matter.
3. The innermost layer is the pia matter
DURA MATER
•The cranial dura is a —— layered tough, fibrous membrane that surrounds the brain.
• It is formed of two layers; ——— and ———.
•The ——— layer is attached to the skull.
•The ——— layer is folded forming the dural folds; ———, and ———
•Sensory innervation of the dura is mostly from the three branches of the ——— and ——— nerves & C— to C—.
DURA MATER
•The cranial dura is a two layered tough, fibrous membrane that surrounds the brain.
• It is formed of two layers; periosteal and meningeal.
•The periosteal layer is attached to the skull.
•The meningeal layer is folded forming the dural folds; falx cerebri, and tentoriam cerebelli
•Sensory innervation of the dura is mostly from the three branches of the trigeminal and vagus nerves & C1 to C3.
Dura matter
Two large reflection of dura extend into the cranial cavity;
Dura matter
Two large reflection of dura extend into the cranial cavity;
-Falx cerebri;
- tentorium cerebelli
Dura matter
-Falx cerebri;
•It is a vertical ——— shaped sheet of dura, in the midline
Extends from the ———- into the ——— fissure between the two ———hemispheres.
•It has an attached border adherent to the ——.
•And a free border lies above the———
Dura matter
Two large reflection of dura extend into the cranial cavity;
-Falx cerebri;
•It is a vertical sickle shaped sheet of dura, in the midline
Extends from the cranial roof into the great longitudinal fissure between the two cerebral hemispheres.
•It has an attached border adherent to the skull.
•And a free border lies above the corpus callosum.
Tentorium cerebelli;
• A horizontal shelf of dura, lies between the posterior part of the ——— hemispheres and the ———.
• It has a free border that encircles the ———.
• Its superior surface in the middle line it is continuous with the ———, separated by the ———
Tentorium cerebelli;
• A horizontal shelf of dura, lies between the posterior part of the cerebral hemispheres and the cerebellum.
• It has a free border that encircles the midbrain.
• Its superior surface in the middle line it is continuous with the falx cerebri, separated by the straight sinus