Skull, Meninges ,Spinal Cord , Ascending Tracts Flashcards
How many bones are found in the neuro-cranium?
14
How many bones are found in the viscerocranium?
14
What bones makes up the neuro-cranium?
F- Frontal bone (1)
E - Ethmoid bone (1)
T- Temporal bone (2)
O- Occipital bone (1)
P - Parietal bone (2)
S- Sphenoid bone (1)
& 6 ossicles
Fill in the blanks.”The upper half of the neuro-cranium consititutes the _______(Vault)
Calvera
What bones make up the Calvera?
- Frontal bone
- Paired parietal bones and with minor participation from sphenoid
- Squamous section of the temporal
- Occipital bone
Which bones form the base of the cranial cavity ?
T- Temporal bone (2)
O - Occipital bone
E - Ethmoid bone
S- Sphenoid bone
“TOES form base of the cranial cavity”
What is the embryological origin of facial bones?
Neural Crest cells
Which bones make up the viscerocranium?
Zygomatic bones 2
Maxillary bones 2
Palatine bones 2
Nasal bones 2
Lacrimal bones 2
Inferior concha 2
Vomer bone 1
Mandible 1
True or False? The mandible is apart of the cranium and facial skeleton.
FALSE!! The mandible is neither a part of the cranium or facial skeleton.
What is the embryological origin of the mandible?
First pharyngeal arch
Fill in the blanks.” The mandible is derived from the first pharyngeal arch mesoderm by perichondral ossification using __________ as a template.
Mechel’s cartilage
When do multiple centers of ossification first appear within the chondrocranium ?
9th week of inter-uterine development
Which bones form the base of the cranial cavity?
Ethmoid bone 1
Sphenoid bone 1
Temporal bones 2
Occipital bone 1
When does the Bregma closes?
18-24 months
When does the Lambda closes?
4-6 months
True or False? The Malleus and Incus are from the First pharyngeal arch while the Stapes and Styloid process are from the Second pharyngeal arch.
TRUE!!
What structure lies deep to the Glabella?
The Frontal air sinuses
Which structures of the viscero-cranium does the maxilla contribute to?
- Upper jaw
- Hard palate ( horizontal plate )
- Lateral wall of nasal cavity
- Floor of the orbit
What type of nerve is the infra-orbital nerve?
Sensory
What type of nerve is the mental nerve?
Sensosry
Which nerve passes through the anterior foramina of the zygomatic bone?
Zygomatico-facial nerve
Which nerve passes through the medial foramina of the zygomatic bone?
Zygomatico-temporal nerve
Which bone contributes mostly to the roof and side of the cranium?
Parietal bone
What structures lies internal to the Pterion?
- The anterior branch of the middle meningeal artery.
- Spheno-parietal dural sinus
- On the left side Broca’s speech area of the brain
Fill in the blanks. “ The ________represent the site of the Sphenoidal fontanelle in infants while the _________ represent the site of location of the mastoid fontanelle in infants.
Pterion - Sphenoidal Fontanelle
Asterion - Mastoid Fontanelle
What is the name of the suture that extends into the frontal bone in the newborn?
Metopic suture (formed from the sagittal suture)
At what age is the Metopic suture completely closed?
7 years
What are the contents of the Temporal Fossa?
Temporalis muscle
Deep temporal nerve (V3)
Blood vessels of muscle
Deep posterior temporal artery
Middle temporal artery
What are the muscles that are apart of the Infra Temporal fossa?
Inferior part of Temporalis Muscle.
Medial and lateral pterygoid Muscle
What are the other contents of the Infra temporal fossa?
Sphenomandibular ligament
Vessel - Maxillary artery and branches
Pterygoid plexus of veins
Nerves- Mandibular nerve and branches
Chorda tympani
Lesser petrosal N.
Otic ganglion
Fill in the blanks. “ The Infra temporal fossa communicates with the pterygo- palatine fossa by way of the ______________.”
Pterygo-maxillary fissure
What are the boundaries of the Infra-temporal fossa?
Anterior - Maxillary bone
Posterior - Articular tubercleof thetemporal & Spina angularisof the sphenoid.
Lateral - Ramus of mandible
Medial - Lateral pterygoid plate
Roof - Greater wing of Sphenoid bone.
Inferior - Medial pterygoid muscle
What is another name for the external occipital protuberance?
Inion
Which muscles attach to the Superior Nuchal line?
Trapezius
Occipitalis
Splenius capatis
and Sternocleidomastoid muscle
” TOSS”
Which muscles are attached to the Inferior Nuchal line?
Obliquus capitis superior muscle
Rectus capitis posterior major muscle
Rectus capitis posterior minor muscle
” InferiORR nuchal line”
Which muscle is attached at the External Occipital Crest?
Ligamentum nuchae
Fill in the blanks. “ Internally within the skull, the transverse dural sinus transition into the _________.”
Sigmoid sinus
Which vessels goes through the incisive foramen?
Nasopalatine nerves
Which muscle is attached to the Posterior nasal spine?
Musculus uvulae
What structure emerges through the Mastoid canaliculus?
Auricular branch of vagus nerve (Arnold’s nerve)
Which two structures form the Straight sinus?
It is a union of the Inferior sagittal sinus which runs in the free edge of the falx cerebri and the great vein of Galen
Fill in the blanks. “ The Great cerebral vein of Galen is formed by the union of __________ &____________.”
The Basal vein of Rosenthal & the Internal cerebral vein.
Where is the Internal cerebral vein formed?
Interventricular foramen of Munro
Which veins come together to form the Internal cerebral vein?
Thalamostriate vein
Septal veins
Choroidal vein.
What are the structures going through the Foramen Magnum?
Spinal cord
Brain stem
Vertebral arteries
Spinal accessory nerves (C1-C5)
Ascending pharyngeal arteries to dura
Fill in the blanks. “ The Basi-sphenoid and Basi occiput are cartilagenous joints that closes at _______.”
At about age 20 years ( 18-23)
What type of joint is the Basi-occiput?
Spheno-Occipital Synchondrosis joint
What structures pass through the Jugular Foramen?
Inf. Petrosal sinus
Cn IX, X, and XI
” 9,10 & 11 goes through Jugular foramen”
Which nerve goes through the Mandibular Foramen ?
Inferior Alveolar nerve
What structure anchors the spinal cord to the coccyx?
Filum terminale
Fill in the blanks. “ Conus medullaris ends between _______ & _______.”
L1 & L2
How many coccygeal spinal nerves are there?
1
How many cervical spinal nerves are there?
8
What attaches the spinal cord to the dura?
Denticulate ligaments
What two structures are formed by the Pia mater?
Filum terminale and denticulate ligaments
What type of fluid is found in sub-arachnoid spaces?
Cerebral spinal fluid
What type of fluid is found in sub-dural spaces?
Serous fluid
Which ganglion is found at the Internal Auditory meatus?
Scarpa’s ganglion
Fill in the blanks. “ The Scarpa’s ganglion contains the first order of neurone for ___________ nerve.”
Vestibular
Fill in the blanks.” Grey matter is divided into ________ while white matter is divided into _________.”
Grey matter - Horns
White matter- Columns (funiculli)
True or False? Grey matter is myelinated axons.
White matter is myelinated axons.
What are connections between left and right halves of the brain?
Commisures
True or False? Anterior root of the spinal nerve consist of Efferent fibres carrying nerve impulses away from the nervous system.
TRUE!!
Anterior root = Efferent = Away
“AEA ( ayeee) “
True or False? The posterior root of the spinal nerve consists of Afferent fibres that carry nerve impulses to the CNS.
TRUE!!
Posterior root = Afferent = Towards
“PAT”
True or False? The anterior root contains sensory fibres while the posterior root contains motor fibres.
FALSE!! Anterior root has Motor fibres while Posterior root has Sensory fibres .
AM & PS
What is the Posterior white columns divided into?
Fasciculus gracilis (medial) and Fasciculus cuneatus (lateral)
What are the different nerve cell groups in the Dorsal Gray column?
- Substantia gelatinosa (apex)
- Nucleus proprius
- Nucleus dorsalis (Clarke’s column)
Which nerve cell group of the Dorsal gray column receives fibers from posterior white column associated with sense of position and movement (proprioception), vibration and two-points discrimination?
Nucleus proprius
Which nerve cell group of the Dorsal Gray column receive afferent fibers concerned with pain, temperature, touch?
Substantia gelatinosa (apex)
Which nerve cell group of the Dorsal Group column are associated with proprioceptive endings (neuromuscular and tendon spindles)?
Nucleus dorsalis (Clarke’s column)
From what spinal nerve roots does Nucleus dorsalis (Clarke’s column) extend from ?
From C8 to L3-4
True or False ? The Nucleus proprius is absent in lumbar and sacral levels.
Fasiculus cuneatus absent in lumbar and sacral levels
Where is the Dorsal root ganglia located?
Dorsal nerve root
What is the Dorsal Root ganglia?
An aggregation of neuron cell bodies located outside the CNS.
What type of cells surround neurone of the PNS ganglia?
Satellite cells
What are the functions of satellite cells?
They provide support, insulate and regulate metabolic change.They are enclosed by connective tissue capsule cells.
What type of neurons are found in the Dorsal root ganglia?
Numerous round unipolar neurons or sensory neurons.
True or False? The Dorsal root ganglia has a nucleus without a nucleolus.
FALSE!!!
What type of information is conducted by the ascending tracts?
Afferent Information .
- Exteroceptive ( originates OUTSIDE the body )
- Proprioceptive ( originate INSIDE the body) .
What is the name of the deep longitudinal fissure found in the spinal cord?
Anterior median fissure
In the anterior gray column nerve cell groups , What are the types of axons are passed out in the anterior root of the spinal nerves and what do they innervate?
- Alpha efferents - which innervate skeletal muscles .
- Gamma efferents - which innervate the lntrafusal muscle fibers of neuromuscular spindles.
What are the three basic nerve cell groups of the Anterior gray column?
- Medial
- Central
- Lateral
Which nerve cell group of the Anterior grey horn is present in most segments of the spinal cord?
Medial group
What is the main purpose for the medial group of the anterior gray horn?
They innervate the musculature of the neck and the trunk, including the intercostal and abdominal musculature .
Which nerve cell group of the Anterior gray horn is responsible for innervating the skeletal muscles for the limbs?
Lateral group
What type of neurons are found in the substantia gelatinosa nerve cell group?
Golgi Type II neurons
Which nerve cell group of the Posterior Gray horn is associated with receiving visceral afferent information?
Visceral afferent nucleus.
Fill in the blanks. “ The Visceral afferent nucleus extends from ____________ to _______”
T1 to L3
True or False? The central canal is closed inferiorly and opens superiorly into the Fourth ventricle.
TRUE!!
Where does the first order neuron have its cell body located?
In the Posterior (Dorsal) root ganglion.
Where is the third order neutron normally located?
In the thalamus
Which neuron gives rise to an axon that decussates and ascend to a higher level of the CNS?
Second order neuron
Which spinothalamic tract is associated with light (crude) touch and pressure?
The anterior spinothalamic tract
What type of sensory information ascends in the Lateral spinothalamic tract?
Painful and Thermal sensations
Discriminative touch (ability to discriminate that 2 areas are being touched simultaneously even is close together ascends in which ascending tract?
Posterior white columns
What also ascends in the Posterior white columns?
Information from muscles and joints pertaining to movements and positions of different parts.
Fill in the blanks. “ Vibratory sensations ascend in the _______.”
Posterior white columns
True or False? . Unconscious informations from the skin, joints, muscles and subcutaneous
tissues reaches the cerebellum by the anterior and posterior spinocerebellar tracts & the Cuneocerebellar tract .
TRUE!!
Pain, Thermal and Tactile information are passed to the superior colliculus of the midbrain through which tract?
Spinotectal tract for Spinovisual reflexes.
What is the function for the Spinoreticular tract?
Provides a pathway for muscle , joints and skin to the reticular information.
Which ascending tract is an indirect pathway for further afferent information to reach the cerebellum?
Spino-olivary tract
What type of fibres are pain impulses transmitted to the spinal cord?
Delta A type fibres & Slow conducting C fibres
For the lateral spinothalmic tract , where does the First order neurons synapse and what substance is normally released?
It synopses in the Posterior Gray column including cells in the substantia gelatinosa.
Substance P is normally released at this synapse.
Which two ascending tracts join together with the lateral spinothalamic tract to from the Spinal Lemniscus?
The anterior spinothalamic tract and the Spinotectal tract.
Where does the Spinotectal tract ascend to?
To the Superior colliculus in the mid-brain.
( The Inferior & Superior colliculus makes up the Tectum in the midbrain hence Spino-TECTAL tract)
Which receptor responds to any stimuli that bring damage to the tissue?
Nocireceptors
Which receptors are associated rods and cones of the retina are sensitive to changes in light intensity and wavelength?
Electromagnetic receptors
Where are Meissner’s corpuscules located?
Dermal papillae of skinof palm and sole of foot
Where are Ruffini corpuscles located?
Dermis of hairy skin
Where are Pacinian corpuscules located?
Dermis, ligaments, joint capsules, peritoneum
True or False? Merckel’s discs are located on Hairy skin?
FALSE!! They are located on HAIRLESS skin
What is the sensory modality for Pacinian corpuscules?
Vibration
Which nuclei is located in the mid-brain?
Substantia nigra and red nucleus
Where does the lateral spinothalamic tract join with the anterior spinothalamic tract and spinotectal tract, forming spinal lemniscus?
In the medulla oblongata
Which two nuclei does the lateral spinothalamic tract lie in between in the medulla oblongata?
Between the inferior olivary and nucleus of the spinal tract of the trigeminal nerve
Where does the spinothalamic tract end by making a synapse with the third-order neuron?
In the Ventral posterolateral nucleus of the thalamus
True or False? In the midbrain, the spinothalamic tract lies in the Tectum.
FALSE!!! It lies in the TEGMENTUM , lateral to the medial leminiscus.
Where does the third-order neurons of the Lateral Spinothalamic tract pass through?
It passes through the posterior limb of the internal
capsule and corona radiata to reach the somesthetic area in the postcentral gyrus of the cerebral cortex.
Where is the second order neurons located for the Fasciculus Gracillis and Fasciculus cutaneous?
Nuclei gracilis and cuneatus of the medulla oblongata
What is the name given to the axons of the second order neurons that crosses the median plane for the Posterior white column?
Internal arcuate fibres
Where is the Somesthetic area located?
In the post-central gyrus of the cerebral cortex
Fill in the blanks.” Fibers of fasciculus gracilis and cuneatus ascend ____________.”
Ipsilaterally
Where do posterior cerebellar fibres receive joint information from?
Muscle spindles, tendons and joint receptors of trunk and lower limbs.
True or False? Most of the fibres of the spinoreticular tracts are uncrossed.
TRUE!!
Where is the third order neurons located for the Spino-olivary tract?
The inferior olivary nuclei in the medulla oblongata
Fill in the blanks. “- Spino-olivary tract conveys information to the __________ from cutaneous and
proprioceptive organs.”
Cerebellum
