cranium, meninges and brain

Question 1

3 cranial fossae of cranial base and parts of brain that sit on them

Answer 1

anterior (frontal lobe), middle (temporal lobes), posterior (cerebellum)

Question 2

what separates anterior and middle cranial fossae

Answer 2

sphenoidal crest

Question 3

what separates middle and posterior cranial fossae

Answer 3

superior border of petrous part of temporal bone

Question 4

superolateral view of cranial base

Answer 4

Question 5

anterior cranial fossa: what separates both orbital part of the frontal bones at cranial base

Answer 5

frontal crest anteriorly, cribriform plate posteriorly (part of ethmoid bone; contains crista galli ridge and foramina, from which olfactory nerves come up from nasal cavity before synapsing at olfactory bulb and returining via olfactory tract)

Question 6

anterior cranial fossa: posteriorly, what is present beneath the orbital parts of the frontal bones and the cribriform plate at the cranial base

Answer 6

body of sphenoid, containing bilateral anterior clinoid processes medially and lesser wing of sphenoid laterally

Question 7

anterior cranial fossa: cranial base diagram

Answer 7

• slightly raised as eye sitting on orbital part of frontal bone
• 2 depressions in frontal lobe (orbital gyrus) as eyes underneath

Question 8

middle cranial fossa: cranial base of middle cranial fossa

Answer 8

• many holes through which cranial nerves go out
• internal carotid artery entry point into cranial cavity at carotid canal (entry point into skull is slightly further away, so artery comes in, turns and then goes up)

Question 9

posterior cranial fossa: cranial base of posterior cranial fossa

Answer 9

Question 10

in brain, dorsal and ventral sections

Answer 10

ventral is below (inferior, where all cranial nerves emerge), dorsal is above (superior); imagine being on all 4s and dorsal coming up back of spine over top of head