Chapter 7 Flashcards
Musculoskeletal System
Bones, muscles and joints
Bones of the adult skeleton are grouped into two principal divisions:
the axial skeleton and the appendicular skeleton
Appendicular Skeleton
bones of the upper and lower limbs. Bones forming the girdles.
Girdles
connect the limbs to the axial skeleton
Short bones
cube-shaped and are nearly equal in
length and width. Consist of spongy tissue except at the surface.
Flat Bones
thin and composed of two nearly parallel plates of compact bone tissue enclosing a layer of spongy bone tissue. Flat bones afford considerable protection and provide extensive areas for muscle attachment.
Irregular Bones
complex shapes and cannot be grouped
into any of the previous categories.
Sesamoid Bones
develop in certain tendons where there is considerable friction, tension, and physical stress, such as the palms and soles.
Sutural Bones
small bones located in sutures (joints) between certain cranial bones.
Surface Markings
structural features adapted for special functions
Two types of surface markings
1)depressions
and openings and 2) Processes
Depressions and Openings
Type of Surface marking. Allow the passage of soft tissues.
Processes
projections or outgrowths that either help form joints or serve
as attachment points for connective tissue. (Ex ligaments and tendons)
Skull
the bony framework of the head. It contains 22 bones (not counting the bones of the middle ears) and rests on the superior end of
the vertebral column (backbone)
Skull bone categories (2)
Cranial Bones and Facial Bones
Cranial Bones
form the cranial cavity, which encloses and protects the
brain.
Facial Bones
form the face: two nasal bones, two maxillae (or maxillas), two zygomatic bones, the mandible, two lacrimal bones, two palatine bones, two inferior nasal conchae, and the vomer.
Frontal Bone
Type of cranial bone. Forms the forehead, the roofs of the orbits, and most of the anterior part of the cranial floor.
Parietal Bone
form the greater
portion of the sides and roof of the cranial cavity. The internal surfaces of the parietal bones contain many protrusions and
depressions that accommodate the blood vessels supplying the dura
mater, the superficial connective tissue (meninx) covering of the brain.
Types of Cranial Bones
Frontal, Parietal, temporal, occipital, sphenoid, and ethmoid.
Temporal Bone
form the inferior
lateral aspects of the cranium and part of the cranial floor. . Projecting from the inferior portion of the temporal squama is the zygomatic process,
which articulates (forms a joint) with the temporal process of the zygomatic (cheek) bone. Together, the zygomatic process of the temporal bone and the temporal process of the zygomatic bone form the
zygomatic arch.
Mandibular Fossa
located on the inferior
posterior surface of the zygomatic process of each temporal bone.
The mandibular fossa and articular tubercle
articulate with the mandible (lower jawbone) to form the:
temporomandibular joint (TMJ)
Mastoid Portion
Part of temporal Bone. located posterior and inferior to the external
auditory meatus (ear canal) which directs sound waves into the ear.
Mastoid Process
is a rounded projection of the mastoid portion of the temporal bone posterior and inferior to the external meatus. Point of attachment for many neck muscles.
Internal Auditory Meatus
The opening through which the facial nerve and vestibulocochlear nerve pass.
Petrous Portion
the temporal portion at the floor of the cranial cavity. Base of skull
Occipital Bone
forms the posterior part and most of the base of the cranium
Foramen Magnum
the inferior part of the occipital bone
Occipital Condyles
articulate with depressions on the first cervical
vertebra (atlas) to form the atlanto-occipital joint, which allows you to
nod your head “yes.”
External occipital protuberance
the most prominent midline projection on the posterior surface of the bone just above the foramen magnum.
Sphenoid Bone
lies at the middle
part of the base of the skull. keystone of the cranial floor because it articulates with all the
other cranial bones, holding them together.
Ethmoid Bone
a delicate bone located in the anterior part of the cranial floor medial to the orbits and is spongelike in appearance.
Ethmoid Bone Forms:
(1) part of the anterior portion of the cranial floor; (2) the medial wall of the orbits; (3) the superior portion of the nasal septum, a partition
that divides the nasal cavity into right and left sides; and (4) most of
the superior sidewalls of the nasal cavity.