C3 - Rhombencephalon Flashcards
1
Q
Define r**hombenchephalon
A
Hindbrain
2
Q
What does the rhombenchephalon consists of?
A
-
Myencephalon (caudal, encloses caudal part of 4th ventricle)
- Medulla oblongata
-
Metencephalon (rostral, above 4th ventricle)
- Pons
- Cerebellum
3
Q
Draw rhombecephalon
A
4
Q
Myencephalon
Structures to mention
A
-
4th ventricle
- Choroid plexus (in medullary velum)
- Cranial nerves (VI through XII)
- Trapezoid body
- Dorsal nucleus of the trapezoid body
- Pyramids
- Nulceus olivaris
- Nucleus gracilis
- Medial cuneate nucleus
5
Q
Myencephalon
- What is myencephalon composed of?
- What does myencephaleon enclose?
A
- It comprises the medulla oblongata
- Encloses:
- Caudal part of the 4th ventricle
- Caudal medullary velum dorsally
6
Q
Myencephalon
Medulla oblongata
A
- Continous with the spinal cord
- Location: fossa medullae oblongata
- Nuclei located in medulla oblongata:
- Nuclei of cranial nerves VI → XII
- Caudal part of nucleus of cranial nerve V
- Corresponding parasympathetic nuclei
- Nuclei of respiratory and circulatory center
- Located close to 4th ventricle within the reticular formation
- The ventral surface is divided into halves by the ventral median fissure
- Pyramidal decussation
- Trapezoid body: at the rostral end of the pyramids
-
Olivary eminence with the olivary nucleus: dorsolateral to the pyramides, at the caudal medulla oblongata
- Role: controlling motor functions of the body
- Functions:
- Coordinating respiration and circulation
- Reflexes:
- Protection of eye
- Coughing
- Swallowing
7
Q
Metencephalon
Structures to mention
A
-
Pons (bridge between mesencephalon and medulla oblongata)
- N. trigemini
- Pontine nuclei
-
Transverse pontine fibers
- Middle cerebellar peduncle
-
4th ventricle
- Rostral medullary vellum
-
Cerebellum
-
Vermis & hemispheres cortex
- Folium
- sulcus
- White matter
- Cerebellar nuclei
-
Cerebellar peduncles
- Rostral
- Middle
- Caudal
-
Vermis & hemispheres cortex
8
Q
Metencephalon
What is the metencephalon composed of?
A
- Pons
- Cerebellum
- Tegmentum metencephali
- Velum medullare rostrale
9
Q
Metencephalon
Pons
A
- Bridge between medulla oblongata and mesencephalon
- Ventral aspect:
-
Sulcus basilaris
- Median groove, produced by right and left pyramidal tracts
-
Pedunculus cerebellaris medialis
- Communication between pons and cerebellum
-
Tegmentum pontis / pars dorsalis pontis
- Floor of 4th ventricle
-
Sulcus basilaris
- Dorsal aspect:
-
Tegmentum ventriculi quarti
- Roof of 4th ventricle
-
Obex
- Unpaired, extends sulcus medianus to medulla oblongata
-
Velum medullare rostrale
- Lamella of white matter between right and left pedunculus cerebellaris rostralis and lingua cerebelli
-
Velum medullare caudale
- Lamina of white matter between right and left pedunculus cerebellaris caudalis, nodulus and tela chordea ventriculi IV
- Tenia ventriculi quarti
-
Tegmentum ventriculi quarti
- The motor nucleus of cranial nerve V (n. trigemini) is located within the pons
- Other nuclei in the pons are responsible for controlling motor funcitons of the body
10
Q
Metencephalon
Cerebellum
A
- Location: above the 4th ventricle
- Connected to the brain stem by 3 peduncles on each side, separated form cerebral hemisphere by transveres fissura → membranous tentorium cerebelli
- Grey matter: cortex
- White matter: medulla
- Cerebellum can be divided into:
-
Vermis
- Lobus rostralis
- Lobus caudalis
- Lobus flocculonodularis
- Lateral hemispheres
-
Vermis
-
Pedunculus cerebellaris caudalis
- Connects cerebellum to medulla
-
Pedunculus cerebellaris medialis
- Afferent fibers from pontine nuclei
-
Pedunculus cerebellaris rostralis
- Attached to midbrain (mesencephalon)
- Afferent fibers
- Function:
- Balance
- Coordination of skeletal muscles
11
Q
4th ventricle
A
- Openings of the central canal
- Fluid-filled cavity
-
Fossa rhomboidea
- Floor of 4th ventricle
-
Velum medullaris rostralis & caudalis
- Thin medullary membranes that extend between fossa rhomboidea and cerebellum like a tent.
- Together with cerebellum: roof over 4th ventricle
12
Q
Tegmentum ventriculi quarti, dog
A
9: Recessus lateralis ventriculi quarti
20: Tegmen ventriculi quarti
21: Velum medullare caudale
22: Velum medullare rostrale
23: Frenulum veil medullaris rostralis
25: Obex
26: Tela choroidea ventriculi quarti
27: Apertura ventriculi quarti
28: Apertura lateralis ventriculi quarti