3 Flashcards
Which vessel contributes to the definitive superior vena cava?
Right common cardinal vein
Which vessel is a primary contributor to the hepatic portal and superior mesenteric veins?
Right vitelline vein
The following blood vessels contribute to inferior vena cava formation. Which one links the subcardinal and supracardinal systems?
Right subsupracardinal anastomosis
The syndrome of left superior vena cava occurs due to which event?
Left anterior cardinal vein persists and right anterior cardinal vein regresses
Which fetal shunt links the umbilical vein with the inferior vena cava?
Ductus venosus
The round ligament of the liver derives from which fetal structure?
Left umbilical vein
Which PNS pathway requires two neurons?
General visceral efferent
Why are smell, taste, vision, hearing and balance considered to be special senses?
Information for each is processed in a separate cortical region
What is the embryonic origin of PNS dorsal root ganglion cells?
Neural crest cells
What is the embryonic origin of PNS somatic motor neurons?
Ventral basal plate neurons
What is the embryonic origin of PNS spinal cord sympathetic preganglionic neurons?
Lateral basal plate neurons
What is the embryonic origin of PNS sympathetic postganglionic neurons?
Neural crest cells
Which support cells predominate in PNS ganglia?
Satellite cells
Which support cells predominate in spinal cord white matter?
Oligodendrocytes
General somatic afferent information travels to the sensory cortex via the dorsal column pathway made up of a sequence of three neurons. the axons of the second neurons extend from the medulla to the thalamus as which tract?
lemniscal tract
The cell bodies of which neurons would be located in the paravertebral (sympathetic chain) ganglia?
visceral motor postganglionic
Primary neurulation produces all of the following cells except?
microglia
Spinal cord alar plate neurons are classified as?
interneurons
Dorsal root ganglion cells, sympathetic chain ganglion cells, sympathetic collateral ganglion cells, adrenal medulla chromaffin cells, Schwann cels and Satellite cells derive from which source?
neural crest cells
Spinal neural tube neuroepithelial cell proliferation results in formation of ventricular, mantle, and marginal layers. How does the mantle layer relate to adult spinal cord structure?
represents gray matter cell bodies
The embryonic tissues produced from secondary neurulation derive from which source?
caudal eminence (tail bud)
Where does cerebrospinal fluid flow?
between the pia and the arachnoid
Somitomeres and somites primarily derive from which source?
paraxial mesoderm
What is the correct order for the spinal meninges?
epidural, dural, arachnoid, subarachnoid, pia
The spinal leptomeninges (arachnoid and pia) derive from which source?
neural crest cells
Failure of the neural tube to close over the entire spinal cord is?
Raschischisis
A vertebral malformation in which the dura and arachnoid layers herniate out of the vertebral canal as a fluid filled sac but the spinal cord is not displaced would be termed?
meningocele
A short, myelinated multipolar neuron would be classified as?
visceral motor preganglionic
The ependymal cells and pia combine to form the roof of the 4th ventricle as the?
tela chordia
Which nucleus is found in the brain stem but not the spinal cord?
special somatic afferent
The inferior ganglion for cranial nerve IX derives from which source?
petrosal placode
Which cranial nerve does not use basal plate derived multipolar neurons to provide general somatic efferent regulation of skeletal muscle?
V
Which cranial nerve does not develop in association with the pharyngeal arches?
III
Which cranial nerve does not provide general somatic afferent information?
III
Which cranial nerve provides general visceral efferent regulation of heart rate?
X
The pharyngeal arch cranial nerves V, VII, IX, and X all contain special visceral efferent fibers. Which other feature do all four share?
all contain placode and neural crest derived afferent neurons
Which area lacks basal plate derived neurons?
diencephalon
Which area is characterized by oculomotor nerve (CN III), red nuclei and substantia nigra?
mesencephalon
The superior and inferior colliculi derive from which definitive brain region?
mesencephalon
The cerebellum derives from which definitive brain region?
metencephalon
The corpus striatum and basal nuclei derive from which definitive brain region?
telencephalon
The pineal gland derives from which definitive brain region?
diencephalon
The optic vesicle derives from which definitive brain region?
diencephalon
The posterior pituitary derives from which definitive brain region?
diencephalon
The cerebral aqueduct characterizes which definitive brain region?
mesencephalon
What is the embryonic origin of the anterior pituitary?
stomodeum surface ectoderm
What is the embryonic origin of the lens vesicle?
placode ectoderm
Why is cerebellum development unique relative to other brain regions?
neuroblasts migrate upward from the ventricular layer and downward from the outer germinal layer
An infant is born with a large mass protruding from the occipital region of the skull. Examination reveals herniation of brain tissue that includes a CSF filled extension of a lateral ventricle. How would you classify this condition?
meningohydroencephalocele
Cerebellar displacement as seen in Arnold-Chiari malformation is associated with which condition?
nonobstructive hydrocephalus
What is the embryonic origin of the corpus striatum?
telencephalon neuroepithelium
What is the embryonic origin of the lens of the eye?
surface ectoderm
The axons of which cells make up the optic nerve?
ganglion cells
The direct differentiation of mesenchyme cells into bone forming cells (osteoblasts) is classified as what type of osteogenesis (bone formation)?
intramembranous
Mesenchyme cell differentiation into cartilage forming cells (chondroblasts) that create a cartilage template, followed by conversion of the cartilage template into bone is which type of osteogenesis (bone formation)?
endochondral
Somites 1-4 are the occipital somites. The 4th occipital somite develops from which somitomere?
11
The vertebra derive from which cell source?
sclerotome
Why is spinal nerve development regarded as segmental while vertebra development is intersegmental?
sclerotome cells from the cranial end of one somite fuse with the caudal end of the next somite
Name three cranial nerves that have special visceral afferent function for taste?
VII facial
IX glossopharyngeal
X Vagus
Name three cranial nerves that have special somatic afferent function and include bipolar neurons? also name the brain region of origin
I olfactory - telencephalon
II optic - diencephalon
VIII vestibulocochlear - metencephalon
Which areas are characterized by the presence of large choroid plexuses?
lateral ventricles
3rd ventricle
4th ventricle
The cornea is made up of an outer epithelium, a middle stroma and an inner endothelium. What is the embryonic origin of these areas?
surface ectoderm
mesoderm
neural crest cells
Identify the four spinal cord alar and basal plate nuclei
Alar: GSA, GVA
Basal: GVE, GSE
Identify the three new nuclei added in the brainstem
SSA, SVA, SVE
List the cranial nerves that develop with the pharyngeal arches by number, name, and ganglia
V trigeminal - semilunar trigeminal ganglion
VII facial - geniculate ganglion; submandibular ganglion
IX glossopharyngeal - petrosal ganglion; otic ganglion
X vagus - nodose ganglion, jugular ganglion (superior); enteric ganglia
superior ganglion - neural crest
How does CNS myelination differ from PNS myelination?
CNS- oligodendrocytes make myelin; 1 cell contributes myelin to many axons
PNS-Schwann cells make myelin; 1 cell contributes myelin to a single axon
What is the fundamental difference between the paleocortex and the neocortex?
The paleocortex forms first and is relatively simple in structure, with three layers of cells.
The neocortex is the new cortex and is more complex in structure, with typically 6 or more layers of cells. The neocortex forms more than 90% of cortical area.
Identify the origin of the cerebellum and cerebrum and explain why the cerebellar cortex and cerebral cortex are unique relative to the brainstem
The cerebral cortex (like the cerebellar cortex) begins development in a pattern similar to that of the spinal cord except that only alar plate cells are present
Identify each of the following:
sulcus limitans
chorda tympani
nucleus of Edinger-Westphal
sulcus limitans- longitudinal lateral grooves in the developing neural tube that separate basal and alar plate neurons
chorda tympani- Pathway for CN VII special visceral afferent fibers for taste from the anterior two thirds of the tongue
nucleus of Edinger-Westphal- mesencephalic GVE nucleus for cranial nerve III. controls pupil constriction
The parasympathetic nervous system contains which nerves?
Describe the fibers?
III oculomotor VII facial IX glossopharyngeal X vagus Sacral - S2-S4 preganglionic- long, myelinated postganglionic-short, unmyelinated
Describe the sympathetic nervous system fibers? contains which nerves?
preganglionic-short, myelinated postganglionic-long, unmyelinated thoracic T1-T12 lumbar L1-L2 T1-L2
The somatic nervous system contains which nerves?
III oculomotor IV trochlear VI abducens XII hypoglossal all spinal nerves (segmental)
How does neuron divergence compare among the somatic, parasympathetic, and sympathetic systems?
somatic- none
parasympathetic- low
sympathetic- high
List the number, name, and basic function of the 12 cranial nerves. Be sure to indicate those with parasympathetic function.
I olfactory - smell
II optic - sight
III oculomotor - eye movement
IV trochlear - eye movement
V trigeminal - facial muscles
VI abducens - eye movement
VII facial - taste, tears, saliva, facial expression
VIII Vestibulocochlear - hearing and balance
IX glossopharyngeal - swallowing, saliva, taste, pain/temperature
X vagus - taste, swallowing, heart rate, respiration, gut motility
XI accessory - neck muscles
XII hypoglossal - tongue muscles, speech, swallowing
List the number, name, and functions of four cranial nerves that use basal plate derived multipolar neurons to provide general somatic efferent regulation of skeletal muscle.
III oculomotor - eye movement
IV trochlear - eye movement
VI abducens - eye movement
XII hypoglossal - tongue muscles
Name the placodes that contribute to formation of cranial nerves I, V, VII, VIII, IX, and X.
I - olfactory placode V - trigeminal placode VII - epipharyngeal (geniculate) placode I VIII - otic placode IX - epipharyngeal (petrosal) placode II X - epipharyngeal (nodose) placode III
List the cranial nerves and major tracts that characterize the pons.
tracts; sensory - lemniscal motor - pyramids - transverse CN V - VII
Which cranial nerves provide SVA for taste in the tongue?
CN VII, IX, X
What is the CSF space that characterizes the pons and medulla?
4th ventricle
List the cranial nerves and major tracts that characterize the medulla?
tracts;
sensory - lemniscal
motor - pyramids
CN VIII - XII
List the cranial nerves, major tracts, and CSF spaces of the mesencephalon.
tracts; -corticospinal (descending) -medial lemniscal (ascending) CSF space is the mesencephalic aqueduct (cerebral aqueduct) CN III and IV
