Download OPT 113 Midterm Exam With Correct Answers!! and more Exams Advanced Education in PDF only on Docsity!
OPT 113 Midterm Exam With Correct Answers!!
neuron nerve that receives, processes and transmits information via electrical and chemical signals
dendrite spiny process that transmits signal to the soma
soma cell body of neuron containing nucleus and other organelles vital for cell function
Axon elongated processes that transmit signal away from soma
retrograde axonal transport move substances from synapse to the soma
anterograde axonal transport movement from soma into and down the axon towards the synapse
terminal button site of synapse for axon of a neuron to dendrite, soma, or axon of another or multiple neurons
neurite
extension from cell body (from dendrite or axon)
multipolar neuron most common in CNS
bipolar neuron a neuron with one axon and one dendrite attached to its soma
pseudo-unipolar neuron -One axon that splits into two branches -most common in PNS -primary sensory neuron
nerve group of axons traveling within nervous system
ganglion group of cell bodies in PNS
nucleus group of cell bodies in CNS
afferent (sensory) neurons signal traveling from peripheral to central nervous system
efferent (motor) neurons
microglia Act as phagocytes, eating damaged cells and bacteria, act as the brains immune system
ependymal cells produce and circulate cerebrospinal fluid
Oligodendrocytes Type of glial cell in the CNS that wrap axons in a myelin sheath
Schwann cells Supporting cells of the peripheral nervous system responsible for the formation of myelin.
Endoneurium connective tissue surrounding axon and nerve fiber
Perineurium connective tissue surrounds fascicle
epineurium
connective tissue surrounding a nerve
Additional features of nerve structure blood vessels, adipose fat tissue, schwann cells
severe neural injury little change in cell morphology and quickly disintegrates
less severe neural injury swelling of soma, displacement of nucleus, movement of Nissl bodies, if cell does not return to normal cytoplasm will appear dark
how are dead neurons removed? microglia (CNS) and macrophages (PNS)
Axon injuries proximal to the soma are usually ______ severe than distal injuries more
degeneration of neuron commences at birth for some axons, continues later on in life due to age
separates occipital lobe from underlying cerebellum
epidural hematoma a hematoma located on top of the dura, shearing of ARTERY
high hydrostatic pressure of arterial blood flow
subdural hematoma pertaining to below the dura mater, shearing of VEIN
lower hydrostatic pressure in veins compared to arteries
these progress much slower than epidural
subarachnoid hematoma Typically occur secondary to a ruptured cerebral aneurysm within the subarachnoid space. Blood mixes with CSF and will raise intracranial pressure.
peripheral nervous system is comprised of somatic (voluntary) control and autonomic nervous system
First step of PNS schema
receptors detect stimuli from inside and outside of the body and send off an electrical signal in response up an afferent (sensory) pathway
Second step of PNS schema electrical signal travels along a chain of neurons through the PNS
Third step of PNS schema afferent signals enter CNS and are organized in a way that yields our perceptions that are stored in CNS as memories
Fourth Step of PNS schema CNS sends out efferent signals along neurons in reponse
Fifth step of PNS schema efferent signals travel through neurons in PNS ending upon effectors (muscles and glands)
CNS ensures the actions of muscles and glands work together to accomplish a common goal
How many pairs of cranial nerves are there? 12
How many pairs of sacral nerves are there? 5
How many pairs of coccygeal nerves are there? 1 pair
Which nerves do not carry motor and sensory information? CN 1 (motor), and coccygeal
Dorsal root sensory axons to CNS
ventral root motor axons from CNS
dorsal root ganglion soma of sensory neurons (pseudo-unipolar type)
prevertebral ganglia sympathetic division of autonomic nervous system
contain synapses of preganglionic and postganglionic sympathetic fibers
white rami carry preganglionic axons (more myelinated) to the sympathetic chain
gray rami unmyelinated postganglionic fibers
preganglionic sympathetic fibers pass directly through the sympathetic trunk without synapsing
post ganglionic sympathetic fibers exiting the preverterbral ganglia innervate viscera in the abdomen and pelvic cavity
Dermatome area of skin supplied by a single spinal cord level or on one side by single spinal nerve
Do all dermatomes have different spinal cord innervations? usually there is a specific region that is supplied by a single spinal cord level
Cervical region the first 7 vertebrae, comprising the neck
thoracic region the 12 vertebrae in the middle of the back
lumbar region lower back
sacral region between lumbar and coccyx region
coccygeal region tailbone or coccyx
Spinal Nerve Plexuses formed by branching and cross joining of anterior rami. Individual nerve fibers do not synapse upon each other
Key somatic plexuses
cervical and brachial plexus
cervical plexus formed from anterior rami of C1-C
Brachial plexus formed from anterior rami of C5-T -severs chest, shoulders, arms and hands
Superior brachial plexus injury head and neck pulled away from arm, waiters tip position
ex) child birth
Inferior brachial plexus injury causes clawing of the hand, pulling of arm that causes problems with muscles of hand
Autonomic visceral nervous system visceral efferent pathway receiving information from hypothalamus in response to visceral afferent information receptors
autonomic ganglia are found along efferent nerve fibers of ANS
how do autonomic ganglia differ from sensory ganglia in ANS ANS axons (preganglionic) enter the ganglia and synapse upon a nerve cell body of a postganglionic neuron
sympathetic ganglia location typically near CNS
Parasympathetic ganglia location near structure of innervation
preganglionic sympathetic nerve fibers leave spinal cord anteriorly and ventrally from T1 to T
sympathetic nerves anywhere in body emerge from spinal nerves in this region
preganglionic parasympathetic fibers leave cranium
via cranial nerves or from sacral portion of spinal cord (cranio sacral)
sympathetic division has paravertebral sympathetic chain of ganglia
Efferent sympathetic axons have preganglionic cell bodies within intermediate horn of grey matter (T1-L2)
one possible destination for preganglionic sympathetic axon synapse with a postganglionic neuron immediately.. axon then exits via grey ramus into the spinal nerve at the same spinal level
another possible destination for preganglionic sympathetic axon ascend or descend in the sympathetic chain and synapse upon postganglionic neuron. Then exists grey ramus
last possible destination for preganglionic sympathetic axon pass through sympathetic chain without synapsing and synapse is one of several ganglia that make up preverterbral ganglia
they will then innervate GI tract or reproductive organ
efferent (motor) preganglionic parasympathetic axons have cell bodies within certain motor nuclei of the brain stem and in certain parts of the sacral spinal cord
