Download - Axial skeleton
The Skeletal System
Composed of the 206 bones in the human body!!
Skeletal System
Functions:1. Support – bears the weight of
the body
2. Protection- skull the brain, ribs=lungs
3. Movement – muscles attach
Skeletal System
Functions:4. Storage *minerals such as calcium & phosphorus are stored and released from bone*fat in yellow bone marrow
5. Hemopoiesis – makes blood cells in red bone marrow
Skeletal System
5 Types of bones categorized by shape:
1. Long bones Longer than wide Bear weight Ex. femur
Skeletal System5 Types of bones categorized by shape:
2. Short bones About same lengthas width Bear weight Ex. Carpels of wristand tarsals of ankle
Skeletal System5 Types of bones categorized by shape:
3. Flat bones Thin and usually curved Protect brain and thoracic
organs Provide wide area muscle
attachment Ex. Ribs, skull, shoulder
blades, sternum,pelvis
Skeletal System5 Types of bones categorized by shape:
4. Sesamoid Small and round Ex. Patella of knee
Skeletal System5 Types of bones categorized by shape:
5. Irregular Odd shaped and doesn’t fit
other categories Ex. vertebra
Skeletal System
Parts of the long bone:
Two main parts:
1. Epiphysis *Found on the ends*Spongy/Cancellous bone
Skeletal System
Parts of the long bone:
Two main parts:
2. Diaphysis• Shaft or long part• Is compact bone
Skeletal System
Types of bone tissue:
1. Spongy bone/Cancellous bone contains networks of bony plates
with spaces - trabeculae not as dense a compact bone
Skeletal System
Types of bone tissue:
2. Compact bone dense and hard Shaft of bone
Skeletal System
Other parts of long bone:
Epiphyseal plate or growth plate:Is hyaline tissue where growth
originates in those under 25 yrs
Epiphyseal line – in adults the epiphyseal plate ossifies or hardens to bone tissue
Skeletal System
Other parts of long bone:
Sheaths – cover the bonea. endosteum – inner most; lines the medullary cavityb. periosteum – outer most; which contains blood vessels and nerves
Skeletal System
Medullary cavity – central cavity of long bone where you find yellow or red bone marrow.
Types of Marrow:
1. Yellow bone marrow – stores fat
2. Red bone marrow – produces red and white blood cells
Skeletal system is divided into two major sections:
1. Axial skeleton – • bones of central axis • Includes 80 bones
• Includes: the skull, vertebral column, and thoracic cage
skull
Vertebral column
Thoracic cage
Vertebral column
Skeletal system divided into two major sections:
2. Appendicular skeleton – bones of upper and lower appendages and bones that attach them to the axial skeleton
Upper appendages and girdles
Lower appendages and girdles
The Skeletal System
Appendicular Skeleton includes:
1. Pectoral girdle joins the upper limbs to the axial
skeleton Includes the clavicle (collar bone)
and scapula(shoulder blade)
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Appendicular skeleton includes:
Pectoral Girdle
Appendicular Skeleton includes:2. Pelvic girdle joins the lower limbs to the axial
skeleton Includes the 2 coxae , sacrum,
coccyx Coxae is formed by the fusion of
3 bones (ilium, pubis, and ischium)
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Coxae
Appendicular skeleton includes:Pelvic gridle
Note three bones of coxae
Sacrum
Appendicular skeleton includes:Pelvic gridle
coccyx
Appendicular skeleton includes:Pelvic gridle
Appendicular skeleton includes:
Lower appendages include:1. Femur Connects to pelvic girdleStrongest bone in body
2. Tibia – larger inner bone of lower leg
3. Fibula – smaller outer bone of lower leg
Bones of Lower Appendage
Appendicular skeleton includes:
Lower appendages include:
4. Patella Knee capActs as a lever to help move the leg
Appendicular skeleton includes:
5. Bones of ankle and foot:
•7 tarsus (ankle)•5 metatarsus (foot)•5 digits (foot) each with 3 phalanges – proximal, middle and distal phalanges except the big toe that has only 2 phalanges only proximal and distal
Ankle and foot:
TarsusTarsals
proximalmiddledistal
Appendicular skeleton includes:
Upper appendage includes:1. Humerus – upper bone that
attaches limb to pectoral girdle
2. Radius – small bone of lower arm that attaches to the thumbs
3. Ulna – small bone that attaches to the little finger and the humerus
Bones of upper appendage
Humerus
Appendicular skeleton includes:
Upper appendage includes:4. Bones of wrist and hand• 8 carpals
• 4 distal carpals• 4 proximal carpals• Articulation of carpals allows
you to move the wrist
5 Bones of the wrist and hand
Carpels
Appendicular skeleton includes:
Upper appendage includes:4. Bones of wrist and hand• 8 carpals
• Metacarpals – 5 long bones of the hand numbered I-V from the medial to lateral
(thumb to little finger)• Digits – made of phalanges
• Three phalanges/finger except thumb has only 2
• Proximal, middle, distal
5 Bones of the wrist and hand
Metacarpals
5 Bones of the wrist and hand
Phalanges
distal
middle
proximal
Terminology:
Proximal – means nearest the body
Distal – means distant (away) from the body
Proximal and Distal
The Skeletal System
Differences between skeleton of child and adult:More bones in youth and fuse together as adult
Epiphyseal plate becomes lineRed bone marrow to yellowArticular cartilage thickens
The Skull or Cranium
The skull protects the brain and entrances to respiratory and digestive systems.
The skull has 28 bones.
The Skull
Terminology:Posterior – back Frontal – frontLateral - side
Inferior – belowSuperior - above
Bones of the Cranium
Parietal
Lateral View
There are two
Occipital
Lateral View
Only one
Temporal
Lateral View
There are two
Sutures – lines or joints between the flat bones of the skulll
Sagittal suture – suture between the two parietal bones, space between when born that closes as develop.
PROCESSES – A PROJECTION OF THE BONE
MASTOID PROCESS – FOUND ON THE TEMPORAL BONES WHERE MUSCLES ATTACH.
Mastoid Process
Lateral View
Frontal View
Frontal
Frontal View
Nasal
Frontal View
Vomer
Frontal View
Zygomaticbone
Frontal View
ZYGOMATIC ARCH –
A PROCESS FROM THE ZYGOMATIC BONE WHICH JOINS A PROCESS OF THE TEMPORAL BONE FORMING AN ARCH.
Maxilla
Frontal View
Mandible
Frontal View
MANDIBLE MOVES - only movable bone in the skull.
MAXILLA AND MANDIBLE ARE USED FOR CHEWING YOUR FOOD
Two bones of eyes socket:
Ethmoid bone and lacrimal bone
Nasal Septum:Vomer and ethmoid
bone form nasal septum which divides the nasal cavity in two .
FrontalParietal
Temporal
Zygoma
Nasal
Vomer
Maxilla
Mandible
Frontal View
Mastoid Process
Lateral View
Frontal
Lateral View
Nasal
Lateral View
Zygomatic
Lateral View
Maxilla
Lateral View
Mandible
Lateral View
Sphenoid
Lateral View
Terminology:
Meatus – a passageway
External auditory meatus – is the passage way that sound waves travel to reach the eardrum.
External Auditory Meatus
Lateral ViewPassageway through which sound waves travel.
Frontal
Nasal
ZygomaMaxilla
Mandible
Parietal
Sphenoid
Temporal
Occipital
External Auditory Meatus
Mastoid Process
Lateral View
A few more things:
Foramen – a hole
Mental foramen – is in the mandible and where the mental nerve passes through.
Sinus – a hollowed out space in the bone.
Nasal cavity – hollowed out, fluid filled regions covered with a thin mucous membrane divided by the vomer and ethmoid bone (septum).
Paranasal sinuses – air-filled spaces connected to the nasal cavities.
Sinuses reduce the weight of the skull, warm air entering body, and affect sound of the voice.
Orbits = eye sockets, house and protect the eye.
Using page 84 in your text label the bones of the cranium
Vertebral Column
Functions:•Protects the spinal cord•Supports the head and neck•Bears body weight
Vertebral Column
It is “S” shaped and acts as a spring or shock absorber to absorb the impact when we walk.
Vertebral Column
It is composed of a series of bones called vertebrae
Vertebral Column
It is marvelously designed to provide strength yet flexibility.
The way the vertebrae fit together the column
is strong yet one can bend and rotatethe back.
Vertebral Column
It is marvelously designed to provide strength yet flexibility.
The way the vertebrae fit together or interlock gives it strength
flexibility so can bend and rotate.
Vertebral Column
It is composed of 5 sections:7 cervical vertebrae12 thoracic vertebrae5 lumbar vertebraeSacrum – 5 fused vertebraeCoccyx – 3 fused vertebrae
sacrum
coccyx
Vertebral Column
Disorders:
At birth vertebral column in concave, and s shape develops.
Scoliosis – abnormal sideways curve of vertebral column.
Vertebral ColumnDisorders:At birth v. column in concave, and s shape developes-Scoliosis – abnormal sideways curve of v. column
Lordosis – exaggerated curve of lumbar – swayback
Vertebral ColumnDisorders:At birth v. column in concave, and s shape developes-Scoliosis – abnormal sideways curve of v. columnLordosis – exaggerated curve of lumbar – swayback
Kyphosis – exaggerated curve of thoracic vertebrae = hunchback
Vertebral Column
Shape of the VertebraeBody – bears weight, bodies rest on each other.
Vertebral Column
Shape of the VertebraeVertebral Foramen – opening through which the spinal cord travels.
Vertebral Column
Shape of the VertebraeVertebral Arch – surrounds the foramen.
Vertebral Column
Shape of the VertebraeProcesses – bone extensions of the vertebrae for muscle attachment and interlock to give mobility.
Transverse process – extends to the sides of each vertebrae,
place for muscle/ ligament attachment.
Vertebral ColumnShape of the Vertebrae
Transverse process – extends to the sides of each vertebrae, place for muscle/ligament attachment.
Spinous process – extends backward and downward, place for muscle attachment.
Vertebral ColumnShape of the Vertebrae
Transverse process – extends to the sides of each vertebrae, place for muscle/ligament attachment.
Superior and inferior articular processes – interlock the vertebrae
Intervertebral Disc - fibrous cartilage found between the vertebrae distributing pressure evenly across the disc.
Herniated Disc - when a disc pushes outside its normal area. Often pinching the nerves causing pain and numbness.
Thoracic Cage
Commonly called the rib cage
Protects the heart, lungs, and other organs of the thoracic cavity
Encloses the thoracic cavity
Thoracic Cage Commonly called the rib cage Protects the heart, lungs, and other organs of the thoracic cavity Encloses the thoracic cavity
Composed of twelve pairs of ribs and the sternum (breast plate or bone)
Thoracic Cage
Types of RibsThe classification of ribs:
1. True ribs – 1st 7 pairs that attach directly to the sternum by the coastal cartilage
Thoracic Cage
Types of RibsThe classification of ribs:
1. True ribs – 1st 7 pairs that attach directly to the sternum by the coastal cartilage
Thoracic Cage
Types of RibsThe classification of ribs:
1. True ribs – 1st 7 pairs that attach directly to the sternum by the coastal cartilage
2. False ribs – inferior 5 pairs that connect indirectly (first 3 pairs) to the sternum or do not attach at all to the sternum (last two pairs)
Thoracic Cage
Types of RibsThe classification of ribs:
1. True ribs – 1st 7 pairs that attach directly to the sternum by the coastal cartilage
2. False ribs – inferior 5 pairs that connect indirectly (first 3 pairs) to the sternum or do not attach at all to the sternum (last two pairs)
Thoracic Cage
Types of RibsThe classification of ribs:
1. True ribs – 1st 7 pairs that attach directly to the sternum by the coastal cartilage
2. False ribs – inferior 5 pairs that connect indirectly (first 3 pairs) to the sternum or do not attach at all to the sternum (last two pairs)
3. Floating ribs – the last two pairs of false ribs that are not attached at all
Thoracic Cage
Types of RibsThe classification of ribs:
1. True ribs – 1st 7 pairs that attach directly to the sternum by the coastal cartilage
2. False ribs – inferior 5 pairs that connect indirectly (first 3 pairs) to the sternum or do not attach at all to the sternum (last two pairs)
3. Floating ribs – the last two pairs of false ribs that are not attached at all
Thoracic Cage
SternumConnects to the ribs via coastal cartilage
Shaped like a capital TFound on the ventral/front surface
Thoracic Cage
Sternum Connects to the ribs via coastal cartilage Shaped like a capital T Found on the ventral/front surface
It consists of three parts, from above downward:
ManubrumBodyXiphoid process
