brain anatomy 1 Flashcards
There are 3 layers that cover the encephalon and the spinal cord, what are they named? From outside to inside
dura, arachnoid, pia mater
What is the encephalon?
The brain
What is the cortex?
the outside layer of the brain
What is the falx cerebri?
het tussenschot tussen de twee hersenhelften (hemispheres). Here the dura is thicker
What is the tentorium cerebri?
Het tentorium cerebelli is een verlenging van het harde hersenvlies die de kleine hersenen scheidt van de onderste delen van de occipitale kwab. The dura is thicker at this part
Where is the subarachnoid space located?
Between the arachnoid and the pia matter
What are subarachnoid trabeculae?
Arachnoid trabeculae. The arachnoid trabeculae are delicate strands of connective tissue that loosely connect the two innermost layers of the meninges – the arachnoid mater and the pia mater. They are found within the subarachnoid space where cerebrospinal fluid is also found.
Which arteries are involved in the circle of Willis? from front to back
Anterior communicating artery
Anterior cerebral arteries
Internal carotid arteries
Posterior communicating arteries
Posterior cerebral arteries
What is the function of the circle of Willis?
The main function of the circle of Willis is to provide a collateral blood flow between the anterior and posterior arterial systems of the brain. Additionally, it offers alternate blood flow pathways between the right and left cerebral hemispheres. This way the circle protects the brain from ischemia and stroke in cases of vascular obstruction or damage.
What is the central and the peripheral nervous system?
central nervous system: brain and spinal cord peripheral nervous system: spinal and cranial nerves
What do oligondrendocytes do?
Oligodendrocytes are cells in the central nervous system (CNS) that play a crucial role in the formation and maintenance of myelin.
What is the difference between oligodendrocytes and schwann cells?
oligodrendocytes produce myelin in the CNS and schwann cells in the PNS
What is the function of astrocytes?
Physical support: Astrocytes provide structural support to neurons by forming a framework for the nervous tissue
What is the function of microglia?
microglia play a critical role in the immune defense of the central nervous system
What are fossae?
In the context of the brain, the term “fossae” typically refers to specific depressions or grooves on the surface of the brain
What are foramina in the brain?
The skull hosts many holes (foramina) to
allow the passage of cranial nerves and vessels.
Name the 3 fossae and where they sit
- anterior fossae (holds part of the frontal lobe)
- medial fossae (does the same for the temporal
lobes)
-occipital fossae (holds the occipital lobe and cerebellum)
Name the 3 section planes of the brain and where they sit
- coronal (in het midden door de breedte)
- sagittal (in de lengte)
- horizontal (horizontaal gesneden)
What is the role of the meninges?
The meningeal role is mainly protective.
In what 2 layers is the dura matter further divided?
- the osteal layer (more toward the skull)
- meningeal layer (more toward the brain)
What is the function of granulations in the subarachnoid space?
These small structures are important for te drainafe of CSF.
Which 2 arteries serve blood to the brain?
- the carotid artery (more ventral)
- the vertebral artery (more dorsal)
When entering the cranial region the vertebral arteries (2 branches) converge into which artery?
When entering the cranial region the vertebral arteries (2 branches) converge into the basilar artery.
From the circle of Willis 3 cerebral arteries depart, which ones?
- anterior
- medial
- posterior cerebral artery
Where do the anterior, medial and posterior cerebral artery send blood to?
- anterior sends to the medial part of the encephalon
- medial sends to the lateral part
- the posterior sends to the occipital part
The brain uses not only blood to survive but also nutrients and salts from the cerebrospinal fluid (CSF). This transparent fluid full of sodium, calcium, magnesium and glucose is produced in the ……
choroid plexus (pia matter invagination that you find at the level of the ventricles)
What are ventricles?
Ventricles are cavities filled by CSF that play a role in distributing the CSF to the whole NS
Name the pathway that CSF undertakes
- CSF is produced in the Plexus choroideus
- it flows trough the ventricles and subarachnoid space via the apertura mediana and lateralis
- it flows trough the cavum subarachnoid
- the csf is absorbed into the sinus via villi and granulations
Name all of the 4 ventricles and the important structures
- 2 lateral ventricles (1 per hemisphere)
- 1 third ventricle (connects the two leteral together)
- a 4th ventricle (a thomboid shape)
between the lateral and the third the foramen of Monro is present for communication.
in between the 3rd and the 4th the cerebral aqueduct is present to spread the csf all the way trough the brain and spinal cord.
after the 4th ventricle we see the central canal
What is the role of sinuses?
to let csf and blood be drained outside the ns
In what disease does an inhibition of drainage of csf result?
hydrocephalus (a disease seen in some kids)
Where is the csf drained after it arrived at the sinuses?
Via the sinuses the CSF is sent, normally
through the sigmoidal sinus to the
jugular vein to leave the CNS.
Name the place of the 4 most important sinuses
- superior sagittal sinus: als een boogschieter naar voren en dan bovenop
- inferior sagittal sinus: als een boogschieter naar voren maar dan eronder
- transverse sinus: door de breedte van het hoofd aan de onderkant
- sigmoidal sinus: beetje gek naar beneden vanaf de transverse sinus
