Structure of the Nervous System Flashcards
How many bones is the skull made up of and what are they?
22 bones
8 form cranium
14 form the face
They are joined together by sutures (fibrous joint)
What are the major parts of the brain?
Triencephalon Diencephalon - thalamus and hypothalamus Mesencephalon - midbrain metencephalon - Pons, cerebellum Myelencephalon - Medulla oblangata
What are the layers of the scalp?
also a mnemonic - SCALP
skin connective tissue epicranial aponeurosis loose areolar tissue pericranium
The first 3 layers are bound together as a single unit.
What is the falx cerebri?
dura mater lies here
What is the tentorium cerebelli?
separates main brain from hindbrain
Where is Broca’s area?
inferior portion of frontal lobe
‘Broc’a - ‘brok’en speech with stroke
What are the 3 meninges?
Dura mater
Arachnid
Pia mater
What is the blood brain barrier and what is the significance in meningitis?
The BBB is a specialised interface between circulating blood and the CNS.
It helps protect the CNS by only allowing certain types of molecules to pass.
Meningitis is the inflammation of the meninges causing it to open, which means some molecules can pass the BBB
Where is the sigmoid sinus?
Just beside mastoid bone (of ear)
form external jugular veins
What passes through the arachnoid membrane?
CSF
What is the ventricular system composed of?
The 2 lateral ventricles (right and left)
3rd ventricle
4th ventricle
What is the significance of the arachnoid granulation?
provides a greater SA for blood or molecules to be exchanged
What is the brain stem and what structures arise from here?
Midbrain
Pons
Medulla
10/12 cranial nerves originate from here.
4-4-2 formation (4 - medulla, 4- pons, 2- midbrain)
How many pairs of cranial nerves are there and what are the key ones to note?
12 pairs
Olfactory nerve (1): olfactory bulbs sit on falx cerebri and go to the limbic system
Optic nerve (2): ‘2 eyes’
- vision
- optic radiations come back to occipital lobe
- chiasm at middle that sits above pituitary gland
Vagus nerve (10): goes everywhere such as lungs, stomach etc
Also facial nerve (7) which controls movement of facial expressions
Look at diagram of cranial nerves
What is the sulcus?
crevice/trench on the brain surface
