Anatomy Lab 8

Skeleton - Axial - Vertebral colum - sacrum; A winglike structure formed by fusion of the transverse processes, articulate laterally with the hip bones. The sacrum is concave anteriorly and forms the posterior border of the pelvis. 

Four ridges cross the anterior part of the sacrum, and sacral foramina are located at either end of these ridges. These foramina allow blood vessels and nerves to pass. 

The vertebral canal contanues inside the sacrum as the sacral canal and terminates near the coccyx via an enlarged opening called the sacral hiatus. 

The anterior border fot he body of S1 is an important anatomical landmark for obstetricians. 

formed from the fusion of three to five small irregularly shaped vertebrae. IT is literally the human tailbone, a vestige of the tail that other vertebrates have. The coccyx is attached to the sacrum by ligaments. 

Skeleton - Axial - Throacic cage; consists of the bony thorax, which is composed of the sternum, ribs and the thoracic vertebrae, plus costal cartilages. Its cone-shaped, cagelike structure protects the organs of the thoracic cavity, including the critically important heart and lungs. 

Skeleton - Axial - Throacic cage; The breast bone is a typical flat bone and a result of the fusion of three bones - the manubrium, body and xiphoid process. 

Skeleton - Axial - Throacic cage - sternum; Supermost portion of the sternum, looks like the knot of a tie and articulates with the clavicle laterally. 

Skeleton - Axial - Throacic cage - sternum; Forms the bulk of the sternum. 

 Skeleton - Axial - Throacic cage - sternum; constructs the inferor end of the sternum and lies at the level of the fifth intercostal space. Although it is made of hyaline cartilage in children, it is usually ossified in adults. 

Underlying physical trauma to the chest can push such a xipoid into the underlying heart or liver, causing massive hemorrhage. 

Skeleton - Axial - Throacic cage - sternum; Jugular notch, sternal angle and the xiphisternal joint. 

Skeleton - Axial - Throacic cage - sternum; Concave upper border of the manubrium can be palpated easily; generally it is at the level of the third thoracic vertebra. 

Skeleton - Axial - Throacic cage - sternum; is a result of the manubrium and body meeting at a slight angle to each other, so that a transverse ridge is formed at the level of the second ribs. Provides a handy reference point for counting ribs to locate the second intercostal space for listening to certain heart vlaves, and is an important anatomical landmark for thoracic surgery. 

Skeleton - Axial - Throacic cage - sternum; the point where the sternal body and xiphoid process fuse, lies at the level of the ninth thoracic vertebra. 

Skeleton - Axial - Throacic cage - ribs; 12 pairs of bones that form the walls of the thoracic cage. 

Via their heads and tubercles and then curve downward and toward the anterior body surface. 

The first seven pairs of ribs called true or vertebrosternal attach directly to the sternum by their own coast cartilages. 

The inferior set of five ribs, they attach indirectly to the sternum or entirely lack a sternal attachment. Of these, rib pairs 8 - 10 which are also know as vertebrochondral ribs, have indirect carilage attachments to the sternum via the costal cartiladge of rib 7. 

Floating or vetebral ribs because they have no sternal attachment. 

Two sets of bones make up the skulls - Cranium and facial bones. 

Enclose and protect the fragile brain tissue. 

Support the eyes and position them anteriorly. Also provide attachment sites for facial muscles which make it possible for us to present our feelings to the world. 

By interlocking joints called sutures - other than the mandible, or lower jawbone, which is attached to the rest of the skull by a freely movable joint. 

Calvaria - forming the superior, lateral, and posterior walls of the skull. 

Cranial base - forming the skull bottom. 

Anterior, middle nad posterior cranial fossae. 

In the fossae completely enclosed by the calvaria. 

Eight bones make up the cranium - 1. Frontal Bone 2.  (2) Parietal bone 3. (2) Temporal bone 4. Occiptal bone 5. Sphenoid Bone 6. Ethmoid bone

Anterior portion of the cranium; forms the forehead, superior part of the orbit, and floor of the anterior cranial fossa. 

Cranium -- Frontal bone -- opening above each orbit allowing blood vessels and nerves to pass. 

Skeleton -- axial skeleton -- Skull -- Cranium -- frontal bone -- Smooth area between the eyes. 

Skeleton -- axial --- skull; posterolateral to the frontal bone, forming sides of the cranium. 

Skeleton -- axial --- skull -- Parietal bone; Midline articulation point of the two parietal bones. 

Skeleton -- axial --- skull -- parietal bone; point of articulation of parietals with frontal bone. 

Inferior to the parietal bone on the lateral skull. 

1. The squamous part - borders the parietals

2. Tympanic part - surrounds the external ear opening

3. Petrous part - form the lateral portion of the skull base and contains the mastoid process. 

Skeleton -- axial --- skull -- temporal bone -- squamous part; point of articulation of the temporal bone with the parietal bone

Skeleton -- axial --- skull -- temporal bone -- squamous part; A bridgelike projection joining the zygomatic bone (cheekbone) anteriorly. Together these two bones form the zygomatic arch. 

Skeleton -- axial --- skull --- temporal bone -- squamous part; rounded depression on the inferior surface of the zygomatic process (anterior to the ear); forms the condylar process of the mandible, the point where the mandible (lower jaw) joins the cranium.