L2 Review of Nervous System Structure & Development; Cranial Bones Flashcards
_____________ (named according to overlying skull bone)
_____________ (folds)
_____________ (furrows)
Lobes (named according to overlying skull bone)
Gyri (folds)
Sulci (furrows)
Two groups of bones in the Cranium?
Neurocranium (protects the brain)
Viscerocranium (assist in formation of face)
Identify the Neurocranial Bones (6)
Identify the Viscerocranial Bones (8)
__________: Groups of nerve cell bodies with similar anatomical connections and functions
PNS vs. CNS?
Nuceli: Groups of nerve cell bodies with similar anatomical connections and functions
GANGLION in peripheral = NUCLEI in CNS
_________: Groups of nerve processes with common connections and functions following the same course
- also called fasciculus, peduncle, lemniscus
- Named according to direction of impulses:
CNS vs. PNS?
Tracts: Groups of nerve processes with common connections and functions following the same course
- also called fasciculus, peduncle, lemniscus
- Named according to direction of impulses:
–e.g. corticospinal tract from “cerebral cortex” to “spinal cord”
–e.g. spinothalamic tract from “spinal cord” to “thalamus”
NERVE in peripheral = TRACT in CNS
Organization of Sensory Pathways: for most somatic senses there are THREE neurons between receptor and perception at cerebral cortex:
- First Order (Primary) Neurons: Send axons into cord or brainstem. Cell body lies in the _____________
- Second Order (Secondary) Neruon: Located in CNS. Axons Projects to _____________ (_____________)
- Third Order (Tertiary) Neuron: Cell body located within specific nucleus of _____________. Axons project to ___________ cerebral cortex (_________________ Cortex)
Organization of Sensory Pathways: for most somatic senses there are THREE neurons between receptor and perception at cerebral cortex:
- First Order (Primary) Neurons: Send axons into cord or brainstem. Cell body lies in the GANGLION
- Second Order (Secondary) Neruon: Located in CNS. Axons Projects to Thalamus (Contralaterally)
- Third Order (Tertiary) Neuron: Cell body located within specific nucleus of thalamus. Axons project to Ipsilateral cerebral cortex (Primary Somatosensory Cortex)
Organization of Motor Pathways: Serquence of TWO neurons between cerebral cortex and effector skeletal muscle
Upper Motor Neurons:
- Cell Body Located in ____________
- Axon Projects via ______________ to Brainstem (_______________)
- Relays to Ventral Horn of spinal cord
Lower Motor Neuron:
- Cell body is located in ____________
- Axons projects to ______________
- AKA the ____________________________________
Organization of Motor Pathways: Serquence of TWO neurons between cerbal cortex and effector skeletal muscle
Upper Motor Neurons:
- Cell Body Located in Motor Cortex
- Axon Projects via Internal Capsule to Brainstem (Decussates)
- Relays to Ventral Horn of spinal cord
Lower Motor Neuron:
- Cell body is located in Ventral Horn
- Axons projects to Muscle Unit
- AKA the Final Common Pathway
In general, each cerebral hemisphere perceives sensations from, and controls movements of, the _____________ side of the body
In general, each cerebral hemisphere perceives sensations from, and controls movements of, the contralateral side of the body
Subdivisions of Primitive Brain
_______________ (Forebrain)
- _______________: Paired vesicles that grow from forebrain => Cerebrum
- ______________: Original part of forebrain => Eye Cup, Thalamus/Hypothalamus
______________ (Midbrain) => ____________
________________ (Hind Brain)
- __________________ =>Pons, Cerebellum
- __________________ (Caudal) => Medulla Oblongota
Prosencephalon (Forebrain)
- Telencephalic Vesicles: Paired vesicles that grow from forebrain =>Cerebrum
- Diencephalon: Original part of forebrain => Eye Cup, Thalamus/Hypothalamus
Mesencephalon (Midbrain) => Midbrain (remains unchanged)
Rhombeencephalon (Hind Brain)
- Metencephalon =>Pons, Cerebellum
- Myelencephalon (Caudal) => Medulla Oblongata
Extreme Cranial End of the primitive brain is the ________________
Extreme Cranial End of the primitive brain is the Lamina Terminalis
What part of the primitive brain gives rise to the Medulla Oblongota?
Rhombeencephalon (Hind Brain)=> Myelencephalon (Caudal) => Medulla Oblongota
What part of the primitive brain gives rise to the Pons/Cerebellum?
Rhombeencephalon (Hind Brain) => Metencephalon => Pons, Cerebellum
What part of the primitive brain gives rise to the Eye Cup and Thalamus/Hypothalamus?
Prosencephalon (Forebrain)=> Diencephalon (Original part of forebrain) => Eye Cup, Thalamus/Hypothalamus
What part of the primitive brain gives rise to the Cerebrum?
Prosencephalon (Forebrain)=> Telencephalic Vesicles (Paired vesicles that grow from forebrain) =>Cerebrum
Telencephalic Vesicles (____________) encloses _____________
Telencephalic Vesicles (Cerebral Hemispheres): LATERAL VENTRICLES
Diencephalon (___________) encloses _________________
Diencephalon (Thalamus): THIRD VENTRICLE
Mesencephalon (___________) encloses ___________________
Mesencephalon (Midbrain): CEREBRAL AQUEDUCT
Metencephalon (____________) encloses ______________________
Metencephalon (Pons & Cerebellum): UPPER PART OF FOURTH VENTRICLE
Myencephalon (___________) encloses _______________________
Myencephalon (Medulla Oblongata): LOWER PART OF FOURTH VENTRICLE
What encloses the Lateral Ventricles?
Telencephalic Vesicles (Cerebral Hemispheres)
What encloses the Third Ventricle?
Diencephalon (Thalamus)
What encloses the Cerebral Aquaduct?
Mesencephalon (Midbrain)
What encloses the UPPER Part of the Fourth Ventricle?
Metencephalon (Pons & Cerebellum)
What encloses the LOWER Part of the Fourth Ventricle?
Myencephalon (Medulla Oblongata)
Mechanism of Neural Tube Formation
- Neural tube Closure BEGINS in the ________ Region and then proceeds _________ and __________
- Temporarily leaves openings called __________ at either end of the tube (anterior & posterior; communicate with amniotic sac)
Mechanism of Neural Tube Formation
- Neural tube Closure BEGINS in the Cervical Region and then proceeds CAUDALLY and CRANIALLY
- Temporarily leaves openings called Neuropores at either end of the tube (anterior & posterior; communicate with amniotic sac)
Timing of Closure of the Neural Tube?
Day 25: Cranial (anterior) Neuropore closes
Day 25 + 2: Caudal (posterior) Neuropore closes
Failure of CAUDAL Closure of Neural Tube?
Spina Bifida
Failure of CRANIAL Closure of Neural Tube?
Anencephaly
Failure of Closure of ENTIRE Neural Tube?
Rachischisis
Surface ectoderm and roof plate produce a protein called bone morphogenetic protein 4 (BMP4) which induces ______ neurone formation and inhibits ________
Surface ectoderm and roof plate produce a protein called bone morphogenetic protein 4 (BMP4) which induces SENSORY neurone formation and inhibits MOTOR
Notochord and floor plate produce a transcription factor called Shh which induces _______ neurone formation and inhibits _________
Notochord and floor plate produce a transcription factor called Shh which induces MOTOR neuron formation and inhibits SENSORY
Cerebellum develops from a special part of the _______________ alar plate called the _______________
Cerebellum develops from a special part of the Mesencephalon’s alar plate called the Rhombic Lip
