1. Cranial Bones, continued….. Sphenoid bone – Wedged between several other bones in anterior portion of cranium – Has a central portion and 2 wing-like structures that extend laterally (???) – Helps form base of cranium, sides of skull, and sides of orbits (“eye sockets”) – Midline of sphenoid bone has a depression (sella turcica) that houses pituitary gland – Contains 2 sphenoidal sinuses

2. Cranial Bones, continued….. Ethmoid bone – Located in front of sphenoid bone – Consists of 2 masses, one on each side of nasal cavity Masses joined by thin cribriform plates (???) Cribriform plates form part of nasal cavity roof. – Crista galli – triangular process between cribriform plates – Perpendicular plate projects downward from cribriform plates helps form nasal septum

3. Cranial Bones, continued….. Ethmoid bone, continued….. – Superior nasal concha and middle nasal concha - project inward from lateral portions of ethmoid bone toward perpendicular plate – Lateral portions of ethmoid bone contain small air spaces (ethmoidal sinuses)

4. Cranial Bones Diagrams 1.Whole class: Label cranial bones on the diagrams of the skull. 2.Choose a color for each of the bones in the cranium (EX: parietal bone = red). 3.Color the bones their assigned color in each diagram.