7 - 1 Chapter 7 Skeletal System. 7 - 2 7.1 Introduction: 7.1 Introduction: A.Bones are very active tissues. A.Bones are very active tissues. B.Each bone

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Chapter 7 Skeletal System

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7.1 Introduction:7.1 Introduction:

A.A. Bones are very active tissues.Bones are very active tissues.

B.B. Each bone is made up of several Each bone is made up of several types of types of tissues and so is an organ.tissues and so is an organ.

C. C. Bone functions include: Bone functions include:

muscle attachmentmuscle attachment

protection and supportprotection and support

blood cell productionblood cell production

storage of minerals.storage of minerals.

CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Which of the following is a function of the Which of the following is a function of the skeletal system?skeletal system?

A.A. Responsible for the transport of oxygenResponsible for the transport of oxygen

B.B. The storage of inorganic saltsThe storage of inorganic salts

C.C. The protection of organs, especially in the The protection of organs, especially in the head and thoraxhead and thorax

D.D. None of these is correct.None of these is correct.

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7.2 Bone Structure

Bones differ in size and shape, yet are similar in several ways.


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Parts of a Long BoneParts of a Long Bone

1.1. Expanded ends of bones that form joints with Expanded ends of bones that form joints with adjacent bones are called adjacent bones are called epiphyses.epiphyses.

2.2. Articular cartilagesArticular cartilages (hyaline cartilage) cover (hyaline cartilage) cover the epiphysesthe epiphyses

3. The shaft of the bone is the 3. The shaft of the bone is the diaphysis.diaphysis.

4. A tough layer of vascular connective tissue, 4. A tough layer of vascular connective tissue, called the called the periosteumperiosteum, covers , covers the bone the bone and is continuous with ligaments and tendons.and is continuous with ligaments and tendons.


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5.5. A bone's shape makes possible its A bone's shape makes possible its function; function; bony processes or grooves indicate bony processes or grooves indicate places ofplaces of

attachment for muscles. attachment for muscles.

*Learn Skeletal Structure Terms *Learn Skeletal Structure Terms

6.6. CompactCompact bone makes up the wall of the bone makes up the wall of the diaphysis; diaphysis; the epiphyses are filled with the epiphyses are filled with spongy bone spongy bone to reduceto reduce

the weight of the skeleton.the weight of the skeleton.

7.7. The diaphysis contains a hollow The diaphysis contains a hollow medullarymedullary cavitycavity that is lined with that is lined with endosteumendosteum and and filled withfilled with

marrowmarrow..


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Microscopic StructureMicroscopic Structure

1.1. Bone cells (Bone cells (osteocytesosteocytes) are located within ) are located within lacunaelacunae that lie in concentric circles that lie in concentric circles around around osteonic canalsosteonic canals..

2. Osteocytes pass nutrients and gasses in 2. Osteocytes pass nutrients and gasses in the matrix through the matrix through canaliculicanaliculi. .

3. Intercellular material consists of collagen 3. Intercellular material consists of collagen and inorganic salts. and inorganic salts.


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4. In compact bone, osteocytes and intercellular 4. In compact bone, osteocytes and intercellular material are organized into osteons that are material are organized into osteons that are cemented together.cemented together.

5. Osteonic canals contain blood vessels and 5. Osteonic canals contain blood vessels and nerve fibers, and extend longitudinally through nerve fibers, and extend longitudinally through bone.bone.

6. Osteonic canals are interconnected by 6. Osteonic canals are interconnected by transverse transverse perforating canalsperforating canals..

7. Unlike compact bone, the osteocytes and 7. Unlike compact bone, the osteocytes and intercellular material in spongy bone are not intercellular material in spongy bone are not arranged around osteonic canals.arranged around osteonic canals.


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Study AnalogyStudy Analogy: Think of it as a sort of apartment : Think of it as a sort of apartment complex or prison system. The osteocytes are complex or prison system. The osteocytes are “trapped” in the hard matrix but are living cells. “trapped” in the hard matrix but are living cells. So everything has to be brought in and out for So everything has to be brought in and out for them. The food and oxygen are sent up “dumb them. The food and oxygen are sent up “dumb waiters” called osteons. The wastes and carbon waiters” called osteons. The wastes and carbon dioxide go down the same way. But each cell is in dioxide go down the same way. But each cell is in its own apartment or jail cell (lacunae) and so the its own apartment or jail cell (lacunae) and so the canaliculi are the way they can pass things back canaliculi are the way they can pass things back and forth from cell to cell so to speak. But they’d and forth from cell to cell so to speak. But they’d better get along! If the first ones “eat up all the better get along! If the first ones “eat up all the food and oxygen” the osteocytes farther out can food and oxygen” the osteocytes farther out can retaliate with their carbon dioxide and by “flushing retaliate with their carbon dioxide and by “flushing their toilets.” their toilets.”


An osteocyte is a An osteocyte is a A. bone building cell.A. bone building cell.B. bone destroying cell.B. bone destroying cell.C. bone cell surrounded by matrix.C. bone cell surrounded by matrix.D. bone marrow cell.D. bone marrow cell.

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The microscopic bony chambers that house The microscopic bony chambers that house mature bone cells are called mature bone cells are called A. lacunae.A. lacunae.B. osteonic canals.B. osteonic canals.C. osteonic systems.C. osteonic systems.D. communicating canals.D. communicating canals.

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Articular cartilage is made from Articular cartilage is made from A. fibrocartilage.A. fibrocartilage.B. endochondral cartilage.B. endochondral cartilage.C. hyoid cartilage.C. hyoid cartilage.D. hyaline cartilage. D. hyaline cartilage.

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7.3 Bone Development and Growth

Bones form by replacing connective tissue in the fetus.

2WAYS: Some form within sheetlike layers of

connective tissue (intramembranous bones), while others replace masses of cartilage (endochondral bones).


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Intramembranous Bones

1. The flat bones of the skull form as intramembranous bones that develop from layers of connective tissue.

2. Osteoblasts deposit bony tissue around themselves.

3. Once osteoblasts deposit bone located in lacunae, they are called osteocytes.

3. Cells of the membranous connective tissue that lie outside the developing bone give rise to the periosteum.


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Endochondral Bones

1. Most of the bones of the skeleton fall into this category.

2. They first develop as hyaline cartilage models and are then replaced with bone.

3. Cartilage is broken down in the diaphysis and progressively replaced with bone while the periosteum develops on the outside.

4. Cartilage tissue is invaded by blood vessels and osteoblasts that first form spongy bone at the primary ossification center in the diaphysis.


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5. Osteoblasts beneath the periosteum lay down compact bone outside the

spongy bone. 6. Secondary ossification

centers appear later in the epiphyses.


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7. A band of hyaline cartilage, the epiphyseal plate, forms between the two ossification centers.

8. Layers of cartilage cells undergoing mitosis make up the epiphyseal plate.

9. Osteoclasts break down the calcified matrix and are replaced with bone- building osteoblasts that deposit bone in place of calcified cartilage.


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10. Epiphyseal plates are responsible for lengthening bones while increases in thickness are due to intramembranous

ossification underneath the periosteum.

11. A medullary cavity forms in the region of the diaphysis due to the activity of

osteoclasts.


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Homeostasis of Bone Tissue

Osteoclasts tear down and osteoblasts build bone throughout the lifespan with the processes of resorption and deposition, with an average of 3% to 5% of bone calcium

exchanged annually.


Blue Box TopicBlue Box Topic

What happened to bone growth if the What happened to bone growth if the epiphyseal plate is damaged before it epiphyseal plate is damaged before it ossifies?ossifies?

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Bone CancersBone Cancers

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Which of the following is not a step in the Which of the following is not a step in the formation of endochondral bone? formation of endochondral bone? A. Hyaline cartilage develops into the shape of A. Hyaline cartilage develops into the shape of the future bone.the future bone.B. Periosteum forms from connective tissue on B. Periosteum forms from connective tissue on the outside of the developing bone.the outside of the developing bone.C. Hyaline cartilage changes to adipose tissue.C. Hyaline cartilage changes to adipose tissue.D. Osteoblasts deposit osseous tissue in place of D. Osteoblasts deposit osseous tissue in place of disintegrating cartilage.disintegrating cartilage.

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Which of the following is an example of an Which of the following is an example of an intramembranous bone? intramembranous bone? A. the parietal bone of the skullA. the parietal bone of the skullB. the phalanges of the fingersB. the phalanges of the fingersC. the humerus of the armC. the humerus of the armD. the femur of the leg D. the femur of the leg

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The cells responsible for removing excess The cells responsible for removing excess bone tissue after the fracture repair process bone tissue after the fracture repair process are are A. fibroblasts.A. fibroblasts.B. chondrocytes.B. chondrocytes.C. osteoblasts.C. osteoblasts.D. osteoclasts. D. osteoclasts.

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Bone that develops between sheetlike layers Bone that develops between sheetlike layers of connective tissue is called of connective tissue is called A. endochondral bone.A. endochondral bone.B. intramembranous bone.B. intramembranous bone.C. cartilaginous bone.C. cartilaginous bone.D. osteoclastic bone.D. osteoclastic bone.

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7.4 7.4 Bone Function Support and Protection

1. Bones give shape to the head, thorax, and limbs.

2. Bones such as the pelvis and lower limbs provide support for the body.

3. Bones of the skull protect the brain,ears, and eyes.


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Body Movement

1. Bones can act as levers.

A lever has four components: rigid barpivot or fulcrumobject that is moved

against resistanceforce that supplies energy


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Blood Cell Formation 1. Two kinds of marrow occupy the medullary cavities of bone.a. Red marrow functions in the formation of red blood cells, white blood cells, and platelets, and is found in the spongy bone of the skull, ribs, sternum, clavicles, vertebrae, and pelvis.b. Yellow marrow, occupying the cavities of most bones, stores fat.


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Storage of Inorganic Salts 1. The inorganic matrix of

bone stores inorganic mineral salts in the form of calcium phosphate that is important in many

metabolic processes.2. Calcium in bone is a

reservoir for body calcium; when blood levels are low, osteoclasts release calcium from bone.


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3. Calcium is stored in bone under the influence of calcitonin when

blood levels of calcium are high.4. Bone also stores

magnesium, sodium, potassium, and carbonate ions.

5. Bones can also accumulate harmful elements, such as lead,

radium, and strontium.



FractureFracture

HematomaHematoma

Cartilaginous callusCartilaginous callus

Bony callusBony callus

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Bone Marrow Transplant (BMT)Bone Marrow Transplant (BMT)

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OsteoporosisOsteoporosis

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Which of the following is usually not found in Which of the following is usually not found in bone? bone? A. potassium.A. potassium.B. calcium.B. calcium.C. lead.C. lead.D. magnesium.D. magnesium.

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7.5 Skeletal Organization

The axial skeleton consists of the skullhyoid bonevertebral column

(vertebrae & intervertebral disks)

(sacrum and coccyx)thorax

(ribs and sternum)


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The appendicular skeleton consists of

pectoral girdle (scapulae and clavicles)

upper limbs (humerus, radius, ulna, carpals,

metacarpals, and phalanges)pelvic girdle

(coxal bones articulating with the sacrum)

lower limbs (femur, tibia, fibula, patella,

tarsals, metatarsals, phalanges)

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Which of the following is NOT included in Which of the following is NOT included in the appendicular skeleton? the appendicular skeleton? A. pectoral girdleA. pectoral girdleB. vertebral columnB. vertebral columnC. upper limbsC. upper limbsD. pelvic girdleD. pelvic girdle

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7.6 Skull

The skull is made up of 22 bones, including

8 cranial bones13 facial bonesmandible

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Cranium 1. The cranium encloses and

protects the brain, provides attachments for muscles, and contains air-filled sinuses that reduce

its weight.2. Features of the frontal bone

(1) include supraorbital foramina and frontal sinuses.

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3. Parietal bones (2) lie at the sides of the skull and join at the sagittal suture.

4. Features of the occipital bone (1) include

the lambdoidal suture, foramen magnum, and occipital condyles.

5. Each temporal bone (2) includes the

squamosal suture, external auditory meatus, mandibular fossae, mastoid process, styloid process, and zygomatic

process.

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6. Features of the winged sphenoid bone (1) include the sella turcica

and sphenoidal sinuses.

7. Features of the ethmoid bone (1) include the cribriform plates, a perpendicular plate, superior and

middle nasal conchae, ethmoidal sinuses, and the crista galli.

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MneumonicMneumonicCranial bones "PEST OF 6":Cranial bones "PEST OF 6":

ParietalParietal EthmoidEthmoid SphenoidSphenoid TemporalTemporal OccipitalOccipital FrontalFrontal The 6 just reminds that there's 6 of them to The 6 just reminds that there's 6 of them to

remember.remember.

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C. Facial Skeleton 14 total1. The 13 immovable

facial bones and mandible form the basic face and provide attachments for muscles of

mastication and expression.

2. The maxillae (2) form the upper jaw,

hard palate, floor of the orbits, sides of the nasal cavity, house the upper teeth, and contain large maxillary

sinuses.

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3. Palatine bones (2) are L-shaped

bones located behind the maxillae

that form the floor of the nasal

cavity and hard palate.

4. Zygomatic bones (2) make up the cheekbones and join with the temporal bones to form the

zygomatic arches.

5. The lacrimal bones (2) form part of

the medial walls of the orbits.

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6. Nasal bones (2) form the bridge of the nose.

7. The vomer bone (1) makes up a portion of the nasal septum.

8. Inferior nasal conchae (2) are fragile, scroll-shaped bones that support mucous membranes within the nasal cavity.

9. The mandible (1), or lower jawbone, supports the lower teeth and includes a mandibular condyle, coronoid process,and alveolar arch.

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Mneumonic: Facial BonesMneumonic: Facial Bones

"Virgil Can Not Make My Pet Zebra "Virgil Can Not Make My Pet Zebra Laugh!"Laugh!"

VomerVomer ConchaeConchae NasalNasal MaxillaMaxilla MandibleMandible PalatinePalatine ZygomaticZygomatic LacrimalLacrimal

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Cleft PalateCleft Palate

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Which of the following is part of the facial Which of the following is part of the facial skeleton? skeleton? A. parietal boneA. parietal boneB. maxillary boneB. maxillary boneC. sphenoid boneC. sphenoid boneD. temporal boneD. temporal bone

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A cleft palate results from incomplete A cleft palate results from incomplete development of the development of the A. palatine bones.A. palatine bones.B. maxillae.B. maxillae.C. mandible.C. mandible.D. vomer bone. D. vomer bone.

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The zygomatic arch is composed of processes The zygomatic arch is composed of processes of the of the A. zygomatic and temporal bones.A. zygomatic and temporal bones.B. zygomatic and maxilla bones.B. zygomatic and maxilla bones.C. maxilla and temporal bones.C. maxilla and temporal bones.D. temporal and parietal bones.D. temporal and parietal bones.

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The hard palate is composed of the The hard palate is composed of the A. sphenoid and ethmoid bones.A. sphenoid and ethmoid bones.B. nasal conchae and vomer bones.B. nasal conchae and vomer bones.C. zygomatic and lacrimal bones.C. zygomatic and lacrimal bones.D. maxillary and palatine bones.D. maxillary and palatine bones.

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7.7 Vertebral Column7.7 Vertebral Column Vertebral Column extends from the skull to the pelvis Vertebral Column extends from the skull to the pelvis

and forms the vertical axis of the skeleton.and forms the vertical axis of the skeleton.

1.1. Composed of vertebraeComposed of vertebrae

2.2. Separated by masses of fibrocartilage called Separated by masses of fibrocartilage called intervertebral discsintervertebral discs

3.3. Connected to one another by ligamentsConnected to one another by ligaments

4.4. Supports head and trunk of bodySupports head and trunk of body

5.5. Protects spinal cord which passes through a Protects spinal cord which passes through a vertebral vertebral canalcanal formed by openings in the vertebrae formed by openings in the vertebrae

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A Typical VertebraA Typical Vertebra

1.1. BodyBody

drum shaped, thick anterior portion of bonedrum shaped, thick anterior portion of bone

2.2. PediclesPedicles

2 short stalks projecting posteriorly from each 2 short stalks projecting posteriorly from each vertebral bodyvertebral body

3.3. LaminaeLaminae

2 plates arise from the pedicles2 plates arise from the pedicles

4.4. Spinous processSpinous process

fusion of the laminaefusion of the laminae

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5.5. Vertebral ArchVertebral Archformed by pedicles, laminae, and spinous formed by pedicles, laminae, and spinous

process process 6. 6. Vertebral ForamenVertebral Foramen

spinal cord passesspinal cord passes7.7. Transverse ProcessTransverse Process

between pedicles and laminaebetween pedicles and laminae8.8. Superior and Inferior Articular ProcessesSuperior and Inferior Articular Processes

cartilage coveredcartilage coveredjoin each vertebra to ones above and below itjoin each vertebra to ones above and below it

9.9. Intervertebral foraminaIntervertebral foraminaopenings provide for spinal nerves between openings provide for spinal nerves between

vertebrae and connect to the spinal cordvertebrae and connect to the spinal cord

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Cervical Vertebrae Neck Region

1. These seven bones are the smallest of the vertebrae that comprise the neck and support the head.

2. The first vertebra is the atlas, which appears as a bony ring and supports the head.

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3. The second vertebra is the axis, with its toothlike dens that pivots within the atlas.

4. Features that separate cervical vertebrae from the rest are the bifid spinous processes and transverse

foramina.

FUN FACTGiraffes and Humans have the same number

of vertebrae in their necks……7.

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Thoracic Vertebrae

Middle of Back

1. Twelve thoracic vertebrae articulate with the ribs.

2. These bones are larger and stronger than the cervical vertebrae.

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Lumbar Vertebrae

Lower Back

1. The five massive lumbar vertebrae support the weight of the body.

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Sacrum 1. The sacrum is a triangular structure at the base of the vertebral column made up of five vertebrae fused into one bone.

2. The spinous processes of these vertebrae fuse to form a ridge of tubercles that have dorsal sacral

foramina along their sides.3. On the ventral surface

of the sacrum, four pairs of pelvic sacral foramina provide passageways for

nerves and blood vessels.

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Coccyx1. The coccyx is the

lowermost portion of the vertebral column and is composed of four fused vertebrae.


Spina BifidaSpina Bifida

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Ruptured DiscRuptured Disc

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The atlas is one of the The atlas is one of the A. lumbar vertebrae.A. lumbar vertebrae.B. thoracic vertebrae.B. thoracic vertebrae.C. cervical vertebrae.C. cervical vertebrae.D. None of these is correct.D. None of these is correct.

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Cervical vertebrae can be distinguished from Cervical vertebrae can be distinguished from other types by the presence of other types by the presence of A. transverse foramina.A. transverse foramina.B. transverse processes.B. transverse processes.C. articulating processes.C. articulating processes.D. vertebral foramina.D. vertebral foramina.

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Which of the vertebrae support the most Which of the vertebrae support the most weight?weight?

A. CervicalA. Cervical

B. ThoracicB. Thoracic

C. LumbarC. Lumbar

D. SacralD. Sacral

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7.8 Thoracic Cage7.8 Thoracic CageA. The thoracic cage includes the ribs, thoracic vertebrae, sternum, and costal cartilages.B. It supports the pectoral girdle and upper limbs, functions in breathing, and protects thoracic and upper abdominal organs.

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Ribs

1. Normally, there are 12 pairs of ribs that attach to the thoracic

vertebrae.

2. The first seven pairs of ribs are true (or vertebrosternal) ribs that join the sternum directly by their costal cartilages.

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3. The remaining five pairs are false ribs: the first three pairs are vertebrochondral ribs, and the

last two pairs are floating ribs.

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4. Features of a typical rib include a shaft, costal groove, anterior (sternal) end, head, neck, and tubercle.

a.The head articulates with the vertebrae; the tubercle articulates with

the transverse process of the thoracic vertebrae.

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Sternum

1. The sternum (breastbone) is located along the anterior midline

of the thoracic cage.

2. It consists of an upper manubrium,

middle body, and lower xiphoid process.

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Ribs that join the sternum directly by costal Ribs that join the sternum directly by costal cartilages are called cartilages are called A. true ribs.A. true ribs.B. false ribs.B. false ribs.C. floating ribs.C. floating ribs.D. All of these are correct. D. All of these are correct.

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7.9 Pectoral Girdle

A. The pectoral girdle makes an incomplete ring that supports the upper limbs.

B. It is made up of two scapulae and two clavicles.

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C. Clavicles

1. The clavicles are elongated S-shaped bones located at the base of the neck that function to brace the

scapulae.

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D. Scapulae 1. The scapulae are flat,

triangular bones on either side of the upper back.

2. A spine divides the scapula into unequal portions.

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3. The spine leads to the acromion process (articulates with clavicle) and coracoid process (provides

attachments for limb and chest muscles).

4. The glenoid cavity articulates with the head of the humerus.

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Which of the following is included in the Which of the following is included in the pectoral girdle? pectoral girdle? A. os coxaA. os coxaB. sternumB. sternumC. sacrumC. sacrumD. scapula.D. scapula.

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7.10 Upper Limb A. Bones of the upper

limb form the framework for the arm, forearm, and hand.

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CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display.B. Humerus

1. The humerus makes up the upper arm, extending from the scapula to the elbow.

2. It articulates with the scapulae at its head, with the radius at the

capitulum, and with the ulna at

the trochlea.3. Other features of the

humerus include the greater and lesser tubercles, intertubercular groove, anatomical

and surgical necks, deltoid

tuberosity, epicondyles, coronoid

fossa, and olecranon fossa.

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C. Radius

1. The radius is located on the thumb side of the forearm, extending from

the elbow to the wrist.

2. The flattened head of the radius pivots with the humerus.

3. Other features of the radius include the radial tuberosity and styloid process.

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D. Ulna

1. The ulna is the longer of the two bones making up the forearm and has a trochlear notch that articulates

with the humerus.2. Other features of the

ulna include the olecranon process, coronoid

process, radial notch, head of the

ulna, and styloid process.

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E. Hand 1. The wrist of the hand

is made up of eight carpal bones bound into a

carpus.2. The framework of the

hand is made up of five metacarpal bones.

3. The fingers are composed of three phalanges in each finger except

the thumb, which lacks the middle

phalanx.

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Mneumonic: Carpals in HandMneumonic: Carpals in Hand"She Looks Too Pretty; Try To Catch Her”"She Looks Too Pretty; Try To Catch Her”

Proximal row then distal row, both lateral-to medial:Proximal row then distal row, both lateral-to medial: ScaphoidScaphoid LunateLunate TriquetrumTriquetrum PisiformPisiform TrapeziumTrapezium TrapezoidTrapezoid CapitateCapitate Hamate· Hamate·

Alternatively: "She Likes To Play; Try To Catch Her".Alternatively: "She Likes To Play; Try To Catch Her". Alternatively: “Some Lovers Try Positions That They Alternatively: “Some Lovers Try Positions That They

Can’t Handle”Can’t Handle”

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Carpal bones: Carpal bones: trapezium vs. trapezoid locationtrapezium vs. trapezoid location

Since there's two T's in carpal bone Since there's two T's in carpal bone mnemonic sentences, need to know which T mnemonic sentences, need to know which T is where:is where:

TrapeziUM is by the thUMB, TrapeziOID TrapeziUM is by the thUMB, TrapeziOID is inSIDE.· is inSIDE.·

Alternatively, TrapeziUM is by the thUMB, Alternatively, TrapeziUM is by the thUMB, TrapezOID is by its SIDE.TrapezOID is by its SIDE.

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7.11 Pelvic Girdle A. The pelvic girdle consists of the two coxal bones and the sacrum; it supports the trunk of the body on the lower limbs.B. The pelvic girdle supports and protects the lower abdominal and pelvic organs.

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C. Each coxal bone is made up of three bones: ilium, ischium, and pubis, that are fused in the region of the acetabulum, the cuplike depression that

articulates with the head of the femur.

D. The ilium is the largest and most superior portion of the coxal bone and joins the sacrum at the sacroiliac joint.

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E. The ischium forms the L-shaped portion that supports weight during sitting.

1. Features of the ischium include the ischial tuberosity and ischial spine.

F. The pubis comprises the anterior portion of the coxal bones and articulates at the symphysis pubis.

1. The large opening, the obturator foramen, lies within each pubis.

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G. The greater pelvis is above the pelvic brim and the lesser pelvis is below it.

H. Structural differences between males and female pelves can be found in Table 7.4.

When the hands are placed on the hips, they When the hands are placed on the hips, they are placed over theare placed over the

A. Iliac crestA. Iliac crest

B. AcetabulumB. Acetabulum

C. Ischial tuberosity.C. Ischial tuberosity.

D. Ischial spine.D. Ischial spine.

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The coxal bones include the The coxal bones include the A. ilium.A. ilium.B. ischium.B. ischium.C. pubis.C. pubis.D. All of these are correct. D. All of these are correct.

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7.12 Lower Limb A. The bones of the lower

limb provide the framework for the thigh, lower leg, and foot.

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B. Femur

1. The femur, or thighbone, extends from the hip to the knee and is the longest bone in the body.

2. Its head articulates with the acetabulum; it articulates with the

tibia at the medial and lateral condyles.

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3. Other features of the femur include the fovea capitis, neck, and greater and lesser trochanters.

4. The patella (kneecap) is located in the tendon that passes over the knee.

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C. Tibia

1. The tibia (shinbone) supports the weight of the body and articulates with the femur (medial and lateral

condyles) and with the tarsal bones of the foot.

2. Its anterior tibial tuberosity is the point of attachment for the patellar ligament.

3. Other features of the tibia include the medial malleolus (innerankle).

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D. Fibula

1. The fibula is a slender bone lying lateral to the tibia; it does not bear body weight.

2. The lateral malleolus forms the lateral ankle.

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E. Foot

1. The ankle is composed of seven tarsal bones, forming a tarsus.

a. The talus articulates with the tibia and fibula.

b. The calcaneus supports the body weight.

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2. The instep of the foot consists of five metatarsal bones and provides an arch.

3. Each toe is made up of three phalanges, with the exception of the great toe,

which lacks a middle phalanx.

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Hip FractureHip Fracture

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The site of most hip fractures is the The site of most hip fractures is the A. head of the femur.A. head of the femur.B. neck of the femur.B. neck of the femur.C. medial epicondyle of the femur.C. medial epicondyle of the femur.D. None of these is correct. D. None of these is correct.

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Which of the following bones is not included Which of the following bones is not included within the lower limb? within the lower limb? A. ulnaA. ulnaB. femurB. femurC. tibiaC. tibiaD. fibulaD. fibula

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7.13 Joints A. Joints (articulations)

are the functional junctions between bones.

B. Joints enable a wide variety of body movements.

C. Joints can be classified according to the degree of movement possible and can be immovable, slightly movable, or freely movable.

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D. Joints can also classified according to the type of tissue that binds them together.

E. Fibrous Joints 1. Fibrous joints are

held close together by dense connective tissue and are immovable (sutures of skull) or only slightly movable (joint between the distal tibia and

fibula).

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F. Cartilaginous Joints

1. Hyaline cartilage or disks of fibrocartilage unite the bones in

cartilaginous joints.2. Intervertebral

disks between vertebrae help absorb shock and are slightly movable.

3. Other examples of cartilaginous joints include the symphysis pubis and the first rib with

the sternum.

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G. Synovial Joints

1. Most joints of the skeleton are synovial joints, which are more complex than fibrous or cartilaginous joints.

2. The articular ends of bone in a synovial joint are covered with hyaline cartilage.

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3. A joint capsule consists of an outer layer of dense connective tissue that joins

the periosteum, and an inner layer made

up of synovial membrane.

a. Synovial fluid has the consistency of egg whites

and lubricates articulating surfaces

within the joint.

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4. Some synovial joints contain shock-absorbing pads of fibrocartilage called menisci.

5. Some synovial joints have fluid- filled sacs called bursae.

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6. Based on the shapes of their parts and the movements they permit, synovial joints can be classified as

follows:a. A ball-and-socket

joint consists of a bone with a globular

or egg-shaped head articulating with the cup-

shaped cavity of another bone; a very wide range of motion is possible; examples include the hip and shoulder joint.

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b. A condyloid joint consists of an ovoid condyle fitting into an elliptical cavity, permitting a

variety of motions; an example is the

joint between a metacarpal and

a phalange.

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c. Gliding joints occur where articulating surfaces are nearly flat or slightly curved, allowing a back-and-forth motion; the joints

of the wrist and ankle, as well as those between

vertebrae, are gliding joints.

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d. In a hinge joint, a convex surface fits into a concave surface, as is found in the elbow and phalange joints; movement is in one plane

only.e. In a pivot joint , a

cylindrical surface rotates within a ring of bone and fibrous tissue; examples include the joint between the proximal ends of the radius and

ulna.

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f. A saddle joint forms where articulating surfaces have both concave and convex areas, permitting a wide range of

movements; the joint between the trapezium

and the metacarpal of the thumb is of this type.

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H. Types of Joint Movements 1. When

a muscle contracts, its fibers pull its movable end (insertion)

toward its stationary end (origin), causing movement at a joint.

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2. These terms describe movements that occur at joints: flexion, extension, dorsiflexion, plantar flexion,

hyperextension, abduction, adduction,

rotation, circumduction, pronation,

supination, eversion, inversion, retraction,

protraction, elevation, and depression.


Rheumatoid ArthritisRheumatoid Arthritis

OsteoarthritisOsteoarthritis

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ArthroscopyArthroscopy

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The joints between the bodies of the vertebrae The joints between the bodies of the vertebrae of the backbone are best described as of the backbone are best described as A. immovable.A. immovable.B. slightly movable.B. slightly movable.C. freely movable.C. freely movable.D. synovial. D. synovial.

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A synovial membrane A synovial membrane A. surrounds the synovial cavityA. surrounds the synovial cavityB. secretes synovial fluidB. secretes synovial fluidC. stores adipose tissueC. stores adipose tissueD. All of these are correct. D. All of these are correct.

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Fluid-filled sacs found between the skin and Fluid-filled sacs found between the skin and underlying bony prominences are called underlying bony prominences are called A. ligaments.A. ligaments.B. menisci.B. menisci.C. bursae.C. bursae.D. None of these is correct. D. None of these is correct.

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Moving the parts of a joint so that the angle Moving the parts of a joint so that the angle between them is increased is calledbetween them is increased is called

A. FlexionA. Flexion

B. ExtensionB. Extension

C. ElevationC. Elevation

D. Abduction.D. Abduction.

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Documents

7 - 1 Chapter 7 Skeletal System. 7 - 2 7.1 Introduction: 7.1 Introduction: A.Bones are very active tissues. A.Bones are very active tissues. B.Each bone