bio 7 skeleton

Axial Skeleton

Central part of the skeleton, includes skull and spine.

Long Bones

Greater length than width, includes humerus.

Short Bones

Cube-shaped, nearly equal length and width.

Flat Bones

Thin bones, protect organs and provide muscle attachment.

Irregular Bones

Irregularly shaped, includes vertebrae.

Sesamoid Bones

Seed-shaped bones, develop in tendons.

Sutural Bones

Small bones located in cranial sutures.

Diaphysis

Long bone shaft, contains medullary cavity.

Epiphysis

Ends of long bones, covered with articular cartilage.

Compact Bone

Dense bone tissue, forms outer layer.

Spongy Bone

Lightweight bone tissue, found inside bones.

Bone Surface Markings

Structural features adapted for specific functions.

Depressions

Surface markings that allow passage of tissues.

Openings

Holes in bones for nerves and blood vessels.

Fissure

Narrow opening between bones for vessels/nerves.

Foramen

Round opening for passage of blood vessels/nerves.

Fossa

Shallow depression in a bone.

Sulcus

Groove or furrow in a bone.

Meatus

Canal-like passageway in a bone.

Cranial Bones

Eight bones forming the skull's protective case.

Facial Bones

Fourteen bones forming the face structure.

Process

Outgrowths forming joints or attachment points.

Condyle

Large rounded projection with smooth articular surface.

Facet

Smooth, flat, slightly concave articular surface.

Head of bone

Rounded articular projection on neck of bone.

Crest

Prominent ridge or elongated projection on bone.

Line

Long, narrow ridge or border on bone.

Spinous process

Sharp, slender projection on vertebrae.

Tubercle

Variably sized rounded projection on bone.

Superior orbital fissure

Passageway for blood vessels and nerves.

Jugular foramen

Opening for jugular vein passage.

Foramen magnum

Large opening for spinal cord entry.

Mandibular fossa

Depression for mandible articulation.

External acoustic meatus

Passageway for sound to the inner ear.

Medial condyle

Inner rounded projection of femur.

Lateral condyle

Outer rounded projection of femur.

Greater trochanter

Large projection on femur for muscle attachment.

Lesser trochanter

Smaller projection on femur for muscle attachment.

Iliac crest

Top ridge of the hip bone.

Linea

Long, narrow ridge less prominent than a crest.

Appendicular skeleton

Comprises 126 bones, including limbs and girdles.

Cranial cavity

Contains 8 bones of the skull.

Auditory ossicles

6 small bones in the ear.

Vertebral column

26 vertebrae forming the spine.

Thorax

1 sternum and 24 ribs.

Pectoral girdles

4 bones connecting arms to the body.

Pelvic girdle

2 bones connecting legs to the body.

Frontal bone

Forms forehead and roofs of orbits.

Frontal squama

Scalelike plate forming the forehead.

Supraorbital notch

Thickened frontal bone, brow line.

Supraorbital foramen

Passage for supraorbital nerve/artery.

Parietal bones

Form sides and roof of cranial cavity.

Temporal bones

Form inferior and lateral cranial aspects.

Zygomatic process

Part of the zygomatic arch from temporal bone.

Mastoid process

Attachment point for neck muscles.

Occipital bone

Contains foramen magnum for spinal cord.

Occipital condyles

Articulate with atlas, forming atlanto-occipital joint.

Sphenoid bone

Articulates with all cranial bones, keystone.

Optic canal

Passage for optic nerve.

Ethmoid bone

Delicate bone forming nasal cavity support.

Cribriform plate

Perforated plate for olfactory nerve passage.

Crista galli

Attachment point for brain membranes.

Perpendicular plate

Forms superior nasal septum portion.

Superior nasal concha

Scroll-like process, increases air surface area.

Middle nasal concha

Turbinates that warm and moisten air.

Non-paired facial bones

Includes vomer and mandible.

Coronal suture

Joint between frontal and parietal bones.

Parietal bone

Bone forming the side and roof of the skull.

Supraorbital margin

Upper edge of the eye socket.

Squamous suture

Joint between temporal and parietal bones.

Temporal bone

Bone forming the sides and base of the skull.

Orbit

Bony cavity containing the eye.

Nasal bone

Forms the bridge of the nose.

Inferior orbital fissure

Opening between the maxilla and sphenoid.

Palatine bone

Forms the posterior part of the hard palate.

Lacrimal bone

Smallest facial bone, contains lacrimal fossa.

Zygomaticofacial foramen

Opening for zygomatic nerve to the face.

Infraorbital foramen

Opening for infraorbital nerve below the orbit.

Zygomatic bone

Forms the cheekbone and lateral orbit.

Maxilla

Upper jawbone, forms part of the orbit.

Perpendicular plate of ethmoid bone

Forms part of the nasal septum.

Alveolar process of maxilla

Contains sockets for upper teeth.

Inferior nasal concha bone

Separate bone that increases nasal cavity surface.

Vomer

Forms inferior part of the nasal septum.

Alveolar process of mandible

Contains sockets for lower teeth.

Mental foramen

Opening for nerves in the mandible.

Mandible

Lower jawbone, largest facial bone.

Nasal septum

Divides nasal cavity into left and right.

Septal cartilage

Cartilage forming the anterior part of the nasal septum.

Temporomandibular joint

Joint between temporal bone and mandible.

Ethmoid

Bone contributing to nasal cavity and orbits.

Orbits

Bony cavities containing the eyes.

Sagittal suture

Joint uniting the two parietal bones.

Lambdoid suture

Joint uniting parietal and occipital bones.

Paranasal sinuses

Air-filled spaces in skull bones.

Functions of sinuses

Lighten skull, resonate voice, moisten air.

Fontanels

Soft spots on an infant's skull.

Anterior fontanel

Soft spot at the front of the skull.

Posterior

Soft spot at the back of the skull.