Sphenoid Bone

What is the sphenoid bone known as

The keystone of the cranium

What is the general structure of the sphenoid bone

A body with three pairs of processes : greater wing, lesser wing, pterygoid process

Where are the sphenoidal sinuses located

The body of the sphenoid bone

What forms the saddle of the sphenoid bone

The sella Turcia

What forms the snug enclosure for the pituitary gland

The hypophyseal fossa; the seat of the sella turcia

What do the greater wings of the sphenoid bone form

Parts of the middle cranial fossa and the posterior walls of the orbits and the external wall of the skull

What do the lesser wings form of the sphenoid bone

Part of the floor of the anterior cranial fossa and part of the medial walls of the orbits

What do the pterygoid processes do

They anchor pterygoid muscles which are important for chewing

What do the optic canals do

Allow passage of the optics nerves (cranial nerves 2) to pass to the eyes

What is the superior orbital fissure

A long slot between the greater and lesser wings; it allows for cranial nerves (3, 4, 5) that control eye movements to enter the orbit

What do the foramen rotundum and foramen ovale provide

Passageways for branches of cranial nerves 5 to reach the face

What does the foramen spinous transmit

The middle meningeal artery

What does the middle meningeal artery do

Served the internal faces of some cranial bones