Name ______Period_____

The Axial Skeleton

The Axial Skeleton

·  Forms the ______of the body

·  Divided into ______

·  ______

·  ______

·  ______

The Skull

·  Two sets of bones

o  ______– encloses & protects brain

o  ______– holds eyes in anterior position & allows the facial muscles to show emotions.

·  All but 1 of the bones are joined by ______

·  Only the ______is attached by a freely movable joint

The Cranium

·  ______– forms ______, brow bone, superior eye orbit

·  ______(___) – form most of the ______of the cranium

o  Meet in midline = ______

o  Meet frontal = ______

·  ______(___)– inferior to parietals & join to them at the ______

o  Important bone markings found here

§  ______– ______leading to eardrum

§  ______– sharp needle-like projection inferior to external auditory meatus (______for many ______)

§  ______– thin ______that joins w/ the zygomatic (______) bone

§  ______– rough projection posterior & inferior to the external auditory meatus

·  ______

·  ______

·  Close to middle ear & ______

§  ______– junction of occipital & temporal

·  Allows for ______

·  Largest vein of the head – ______

§  ______– anterior to jugular foramen

·  Transmits ______(facial & vestibulocochlear)

§  ______- anterior to jugular foramen

·  ______

·  ______– most posterior bone of cranium forming ______

o  Joins parietals anteriorly at ______

o  ______ = large opening in base of the occipitals (______)

§  Lateral to the foramen magnum are rockerlike ______

______which rest on the 1st vertebra

·  ______ – butterfly-shaped – spans the width of the skull and forms part of ______

o  ______“Turk’s saddle” = small depression on the midline of the sphenoid, holds the ______

o  ______= large oval opening in line w/ the posterior end of the sella turcica (allows ______(trigeminal) to pass to ______muscles of mandible

o  Parts of the ______form part of the eye orbits

§  2 important openings:

1.  ______ (optic nerve)

2.  ______ (cranial nerves 3, 4 & 6 – eye movements)

o  Central part of the sphenoid riddled w/ air cavities = ______

·  ______– irregularly shaped, anterior to sphenoid – forms ______and ______.

o  ______“cock’s comb” = superior ethmoid surface projection – ______

o  ______– holey areas on sides of crista galli= ______pass through from nose

o  ______– extensions of the ethmoid – form part of ______& ______of air flowing

Facial Bones

*______

*______, only the ______and ______are ______

·  ______(___) / maxillary bones – fused to form ______

o  Upper teeth carried in the ______

o  ______– extensions that form the ______part of the ______

o  ______– ______

______, lighten the skull bones, ______as we speak

§  Hollow portions of bones surrounding the nasal cavity

§  ______(infection of sinuses) – can result in ______pain

·  ______(___) – posterior to palatine processes of maxillae – form ______part of ______

o  ______= failure of these to fuse

·  ______(___) – cheek bones – form portion of ______

______

·  ______(___) – fingernail sized bones forming part of ______

______

o  Groove serves as ______

·  ______(___) – small rectangular bones – form ______– lower part of nose made of cartilage

·  ______“______” (1) – median line of nasal cavity – forms ______

______

·  ______ (___) – thin, ______

______from lateral walls of the nasal cavity

·  ______(lower jaw) – largest, ______– ______on each side of face, forming the ______(find them!)

o  Horizontal part (body) forms the ______

o  2 upright bars of bone (rami) extend from the body to connect the mandible with the temporal bone.

o  ______lie in ______

The Hyoid Bone

·  ______

·  ______w/ a body and 2 pair of horns (cornua)

·  Closely related to mandible and temporal bones

·  ______

______

·  Suspended in mid–neck region 2 cm above the larynx, ______

______

·  Serves as a movable ______& attachment point for neck muscles (lower and raise larynx when we swallow & speak)

The Fetal Skull

·  Face small compared to size of cranium (skull is large compared to body length)

·  ______

______; newborn is ______

·  ______ – fibrous membranes connecting the cranial bones

o  Baby’s pulse can be ______spots (explains their name “little fountain”)

o  Allow fetal skull to be ______

o  Allow infants ______

o  Largest fontanels are diamond shaped anterior shaped fontanel and smaller triangular shaped posterior

o  ______

______after birth

The Vertebral Column

·  Serves as ______of the body

·  Extends ______, which it supports, ______, where it transmits the weight of the body to the legs.

·  ______connected & ______creating a flexible, curved structure.

·  ______runs through central cavity, protected by vertebrae

·  ______= ______but ______

______– the ______(5 fused) & the ______(4 fused).

·  Each vertebrae is given a ______

______

.

·  24 single vertebrae

o  ______vertebrae

o  ______vertebrae

o  ______vertebrae

·  Vertebrae separated by pads of ______– ______discs – ______while ______.

o  ______person – discs = ______– ______.

o  As you ______– ______– ______

·  Can ______.

·  Can ______from ______

·  ______on ______= ______& excruciating ______

·  ______& ______of spine ______to head when we walk or run.

o  ______curvatures

·  ______regions

·  ______

o  ______curvatures

·  ______curvature appears ______

______

·  ______curvature when baby ______

·  ______spinal curvatures

o  ______- abnormal ______of the spine.

o  ______- Abnormal ______of the spine, resulting in ______.

o  ______- Abnormal ______of the spine in the ______region.

Vertebrae

·  All vertebrae have a similar structural pattern.

o  ______: disclike, ______part facing anteriorly.

o  ______: formed from the joining of all posterior extensions, the laminae & pedicles.

o  ______: ______through which the spinal cord passes.

o  ______: 2 lateral projections from the vertebral arch.

o  ______: single projection arising from the posterior aspect of the vertebral arch (fused laminae).

o  ______

______: ______projections lateral to the vertebral foramen allowing a ______

______.

Cervical Vertebrae

·  7 (______) – form the ______region.

·  First 2 – ______– are different because they perform functions not shared by any other cervical vertebrae.

·  ______(C1) has ______; the superior surfaces of its transverse processes contain large depressions that ______

______; allows you to nod “______.”

·  ______(C2) has a ______(______or ______), which acts as a ______; allows you to indicate “______.”

·  C3 through C7 are the smallest, lightest vertebrae

·  All transverse processes ______through which ______pass to the brain.

Thoracic Vertebrae

·  ____ with body somewhat ______w/ ______

______, which receive the heads of the ribs.

·  ______is long & ______(from the side looks like a ______head).

Lumbar Vertebrae

·  ___ w/ massive ______& ______(looks like ______head from side).

·  ______vertebrae – ______

______.

Sacrum

·  Formed by the ______.

·  Winglike ______laterally ______forming the ______.

·  Forms the ______.

·  ______ roughens the posterior midline & are flanked by ______.

·  Vertebral canal continues inside the sacrum as the ______– terminates in large inferior opening called the ______.

Coccyx

·  Formed by ______, irregularly shaped vertebrae

·  This is the human “______” – a remnant of the tail other vertebrate animals have.

Bony Thorax

·  Made-up of three parts

o  ______

o  ______

o  ______

·  Often called the “______” b/c it forms a ______

______of slender bones to protect the major organs of the thoracic cavity.

·  ______– “breastbone”

o  Flat bone that is a result of the ______– the ______

o  ______to the ______

o  Three important bony landmarks:

1.  ______ (concave ______border of the ______) – can be felt easily – generally at ______

2.  ______ - where manubrium & body meet - formed at level of ______(reference to locate ______

______ for ______)

3.  ______ – body and xiphoid process fuse (level of ______)

o  ______used to get bone marrow tissue to ______

·  Ribs – ______– form walls of bony thorax

o  Articulate w/ vertebral column posteriorly & curve downward toward anterior body surface.

o  ______= ______– ______to sternum by ______

o  ______= ______– ______

______(______are called “______” b/c they are the ones not attached at all)

o  Contrary to popular myth – men & women have the same number of ribs!! J