Bones of the Skull

Question 1

The upper portion of the skull. It divides into two regions: the braincase that houses and protects the brain, and the rostrum that includes the upper jaw and bones that surround the nasal passages.

Answer 1

Cranium

Question 2

The lower jaw. It is composed of two bones - the left and right dentary.

Answer 2

Mandible

Question 3

An immovable contact zone between two bones.

Answer 3

Suture

Question 4

A projection or protuberance from a bone that serves as a point of attachment for muscles.

Answer 4

Process

Question 5

A rounded protuberance of bone that serves as an articulation point with other bones.

Answer 5

Condyle

Question 6

A canal that penetrates a bone and allows for passage of nerves and blood vessels.

Answer 6

Foramen

Question 7

A pit or depression in a bone; the site of attachment for muscles or for articulation with another bone.

Answer 7

Fossa

Question 8

The socket in the skull where the eyeball is situated.

Answer 8

Orbit

Question 9

Paired bones located inside the nasal passages; looks spongy.

Answer 9

Turbinate

Question 10

Paired bones anterior to the maxillae. Hold the incisors.

Answer 10

Premaxilla

Question 11

Paired bones posterior to the premaxillae. Hold all upper teeth except for incisors.

Answer 11

Maxilla

Question 12

Paired bones between the maxilla and frontals. Dorsal to the maxillae.

Answer 12

Nasal

Question 13

Paired bones between the nasals and parietals. Help form the dorsal part of the braincase.

Answer 13

Frontal

Question 14

Paired bones at the juncture of the maxillae, frontals, and jugals.

Answer 14

Lacrimal

Question 15

Paired bones that form the anterior-most portions of the zygomatic arches. Between the maxillae and squamosals.

Answer 15

Jugal

Question 16

Paired bones between the frontals and supraoccipital. Help form the roof of the braincase.

Answer 16

Parietal

Question 17

Single bone between the parietals and supraoccipital. Not present in many mammals.

Answer 17

Interparietal

Question 18

Paired bones that form the posterior most portions of the zygomatic arches and the lateral walls of the braincase. Between the jugals, parietals, and occipital bones.

Answer 18

Squamosal

Question 19

Paired bones on the ventral surface of the cranium. Between the maxillae and the pterygoids. Form the “roof of the mouth.”

Answer 19

Palatine

Question 20

Single bone that forms the floor and septum of the nasal cavity. Anterior to the prephenoid.

Answer 20

Vomer

Question 21

Single, complex bone between the vomer and the basisphenoid. Parts of the bone help form the lateral walls of the braincase.

Answer 21

Presphenoid

Question 22

Paired bones consisting of thin sheets that are situated on top of the presphenoid and alisphenoid bones.

Answer 22

Pterygoid

Question 23

Paired bones to the sides of the prephenoid and basisphenoid. Parts of these bones help form the lateral braincase.

Answer 23

Alisphenoid

Question 24

Single bone between the presphenoid and the basioccipital.

Answer 24

Basisphenoid

Question 25

Single bone between the foramen magnum and the basisphenoid.

Answer 25

Basioccipital

Question 26

Paired bones between the supraoccipital and the foramen magnum. The occipital condyles are always attached here. Help form the rear of the braincase.

Answer 26

Exoccipital

Question 27

Single bone between the parietals and the exoccipitals. Helps form the rear braincase.

Answer 27

Supraoccipital

Question 28

Paired bones that form the lower mandible. Hold all of the lower teeth.

Answer 28

Dentary

Question 29

Space between the incisors and the molariform teeth. Only occurs in species that lack canines.

Answer 29

Diastema

Question 30

Uppermost process on the dorsal projection of the dentary.

Answer 30

Coronoid process

Question 31

Rounded process on the dentary that articulates with the glenoid fossa on the squamosal. Always between the coronoid process and the angle of the jaw.

Answer 31

Mandibular condyle (condyloid process)

Question 32

Posterior most projection of the dentary. Always below the condyloid process.

Answer 32

Angle of the jaw

Question 33

Depression in the squamosal bone where the dentary bone articulates.

Answer 33

Mandibular fossa (glenoid fossa)

Question 34

Opening in the base of the braincase through which the spinal cord passes.

Answer 34

Foramen magnum

Question 35

Downward pointing, spike-like projection of the exoccipital bone. Located directly behind the auditory bullae.

Answer 35

Paraoccipital process

Question 36

Smooth raised surface on the exoccipital bone where the skull articulates with the first vertebrae

Answer 36

Occipital condyles

Question 37

Bony capsule enclosing the middle ear.

Answer 37

Auditory bullae

Question 38

Passage leading from external ear opening to the eardrum

Answer 38

External auditory meatus

Question 39

A ridge on the dorsal surface of the skull that extends rearwards from the orbits the edge of the supraoccipital bone.

Answer 39

Sagittal crest

Question 40

Ridge extending laterally across the skull along the juncture of the parietals and the supraoccipital.

Answer 40

Lambdoidal crest

Question 41

An arch of bone formed by the jugal and squamosal that extends from the rostrum to the braincase. Forms the case of the orbit and protects the eye.

Answer 41

Zygomatic arch

Question 42

A pit or open space located just anterior to the lacrimal. Characteristic of cervids.

Answer 42

Prelacrimal vacuity

Question 43

Maxilla where the bone has numerous small openings or honeycombs.

Answer 43

Fenestrated maxilla

Question 44

Hole in the roof of the mouth at the juncture of the premaxilla and maxilla.

Answer 44

Incisive foramen

Question 45

An opening in the maxilla that leads into the orbit.

Answer 45

Infraorbital foramen

Question 46

Projection from the frontal bone behind/above the orbit.

Answer 46

Postorbital process