Age of DinosLab II

The Vertebrate Skeleton

The Functions of the Skeleton

•A reservoir of chemicals needed in metabolism

•A structural support for soft tissue

•Armor for vulnerable body parts

•A framework upon which muscles may act to facilitate movement

Bone

•Composed of mineral and protein

•Mineral is hydroxyapatite, a calcium phosphate compound

•Proteins structure is complex and includes several substances

Divisions within the skeleton

•Axial skeleton

•bones of the skull and vertebral column

•Appendicular skeleton

•bones of the limbs and limb girdles

The Skull

•Houses brain and sensory organs

•Houses feeding structures

•Houses muscles that operate the jaw

Openings for the Spinal Chord

•Foramen Magnum

•means ‘big hole’

•opening at the back of the skull where the spinal chord exits

Openings for Sensory Organs

•Naris

•bony opening for the nostril

•Choana

•Bony opening on the palate that communicates with the Naris

•Orbit

•Bony eye socket

Openings for the Jaw Muscles

•Temporal Region

•part of skull behind the orbit

•houses braincase and muscles of the jaw

•Abductor Chamber

•Part of the temporal region where jaw muscles attached

Fenestrae

•Openings in the skull that allow muscles to get bigger

•Four major groups of Fenestrae

•Posttemporal

•Infratemporal

•Supratemporal

•Mandibular

Openings for Air Sacs

•These chambers are called pneumatic

•Filled with air

•Function unknown

•Two major groups

•Antorbital fenestra

•Maxillary fenestra

The Vertebral Column

•Cervical Vertebrae

•vertebrae of the neck

•Dorsal Vertebrae

•vertebrae of the back

Vertebrae (cont.)

•Sacral Vertebrae

•pelvic bones are solidly attached to these

•Caudal Vertebrae

•vertebrae of the tail

Ribs

•Ribs are attached to most vertebrae

•Called either cervical, dorsal, sacral, or caudal ribs

Haemal arches

•Found below caudal vertebrae

•Have a V-shaped profile from the front

•Look like commas from the side

Pectoral Girdle

•Scapula

•the shoulder game

•Coracoid

•greatly reduced in mammals

•abuts the scapula

Pectoral Girdle (cont.)

•Glenoid Fossa

•socket in the scapula and the coracoid that abuts the humerus

•Clavicle

•the collar bone

The Forlimb

•Humerus

•upper arm bone

•Radius

•one of two lower arm bones

•on the same side as your thumb

The Forelimb (cont.)

•Ulna

•one of the bones of the lower arm

•forms the elbow

•looks like a wrench

The Forelimb (cont.)

•Carpals

•bones of the wrist

•Metacarpals

•long bones of the hand

•Phalanges

•bones of the fingers

The Pelvic Girdle

•Acetabulum

•hip socket formed from the junction of the three pelvic bones

•Ilium

•forms the upper third of the acetabulum and extends above it

The Pelvic Girdle (cont.)

•Pubis

•Forms lower part of acetabulum

•Ischium

•forms lower rear part of acetabulum

The Hindlimb

•Femur

•Large bone of the upper leg

•Fibula

•the outer long bone of the lower leg

•much smaller than the tibia

The Hindlimb (cont.)

•Tibia

•inner bone of the lower leg

•much larger than the fibula

•Tarsals

•ankle bones

The Hindlimb (cont.)

•Metatarsals

•long bones of the foot

•Phalanges

•bones of toes