Microscopic Image
of Bone Cells:
The Skeletal System
ANATOMY &
PHYSIOLOGY
http://micro.magnet.fsu.edu/primer/techniques/phasegallery/images/humanpathology/humanbone.jpg
The Skeletal System:
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Contains bones, the
organs of this system
The tissues of this
system: bone tissue,
cartilage, blood,
connective tissue &
nervous tissue
Bones, no matter their
location or size, have
similar functions and
structure
http://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/9065.
jpg
Functions of Bones:
1.
2.
3.
4.
5.
Support: provide framework for the body and
surround organs
Protection: enclose soft organs
Movement: Along with skeletal muscles and
tendons, enable the body to move.
Storage: Within the bone marrow (middle of the
bone), Ca++ and P are stored.
Blood Cell Formation: Within the bone marrow,
blood cells are formed; a.k.a. hematopoiesis.
Classification of Bones:
There are 206 bones
in an adult body.
There are 2 types of
bone:
 Compact Bone: dense
 Spongy Bone, a.k.a.
Cancellous Bone: open
spaces within the
bone
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There are 4 groups of
bones:
 Long
 Short
 Flat
 Irregular
Types
of
Bones:
http://www.google.com/imgres?
Structure of the Bone:
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http://www.google.com/imgres?
The diaphysis is the
‘shaft’ of the bone
(bone length); mainly
compact bone.
The epiphysis are the
ends (of long bones);
mainly spongy bone.
The periosteum is the
bone covering, or
membrane.
Structure of the Bone:
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Red Marrow forms blood cells; this is found within the
epiphysis of some long bones and in spongy bone of
flat bones.
Yellow marrow (fat) is found within the medullary cavity.
http://www.google.com/imgres?
Microscopic Structure of the Bone:
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Osteocytes are mature bone cells.
These are found w/in lacunae (cavities) which form
circles called lamellae.
Lamellae form around Haversian (or osteonic) canals.
Canaliculi allow a ‘transportation’ system for the bone
cells (to receive blood and nutrients).
Perforating (or Volkmann’s) canals allow communication
to occur.
http://www.google.com/imgres?
http://www.web-books.com/eLibrary/Medicine/Physiology/Skeletal/compact_spongy_bone.jpg
Bone Formation:
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Osteo means bone.
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Most bones form from hyaline cartilage.
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This process is called ossification.
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Bone forming cells are called osteoblasts.
Skeletal Organization:
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Look up labeled diagram in text or online: KNOW
THIS FIGURE!
2 major portions of the skeleton: axial skeleton
(bones & cartilage of the head & trunk) and the
appendicular skeleton (bones & cartilage of the
limbs).
There are 206 bones in the (adult) body.
http://www.google.com/imgres?
Axial Skeleton: The Skull:
Cranium encloses the
brain
Includes:
 Frontal bone
 Parietal Bones (2)
 Temporal Bones (2)
 Occipital Bone
 Sphenoid Bone
 Ethmoid Bone
http://www.google.com/imgres?
Axial Skeleton: The Skull:
Facial Bones, including:
 Mandible
 Nasal Bones
 Maxillary Bones
Hyoid Bone: suspended
in the midneck above
the larynx.
http://www.google.com/imgres?
Axial Skeleton: The Vertebral Column (Spine):
Contains 33 vertebrae
 9 of these are fused (form 2
bones):
 Sacrum and Coccyx (tailbone)
 Cervical vertebrae are in the
neck region (1st 7)
 Thoracic vertebrae are in the
trunk (next 12)
 Lumbar vertebrae are in the
lower back (the last 5)
http://www.google.com/imgres?
Axial Skeleton: Thoracic Cage:
Protects the heart, lungs, and major BVs.
Includes:
1. Sternum (breastbone)
 This is attached to the 1st 7 pairs of ribs.
 The heart is posterior to the sternum.
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Axial Skeleton: Thoracic Cage:
2. 12 pairs of Ribs:
 True ribs are attached to
the sternum (1st 7)
 False ribs (next 5)
 Last 2 pair are a.k.a.
‘floating ribs’ b/c they
lack attachment to
sternum.
 ALL ribs are attached to
vertebral column!
http://www.google.com/imgres?
Appendicular Skeleton: The Shoulder:
Shoulder, or pectoral,
girdle contains:
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Clavicle (collarbone)
Scapula (shoulder
blade)
http://www.google.com/imgres?
Appendicular Skeleton: The Upper Limbs:
The bones of the upper limb
are:
 Humerus (arm)
 Radius (thumb to forearm)
 Ulna (pinky finger to
forearm)
 Hand: Carpels (wrist),
metacarpels (palm), and
phalanges (fingers)
http://www.google.com/imgres?
Appendicular Skeleton: The Pelvic Girdle:
Contains:
 Coxal Bones (hip
bones) which are
composed of the
ilium, ischium, and
pubis
http://www.google.com/imgres?
Appendicular Skeleton: The Lower Limbs:
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http://www.google.com/imgres?
The thigh bone is a.k.a. the
femur.
The leg bones are the tibia
(shinbone; larger), fibula
(thinner), and patella
(kneecap).
The foot contains the tarsal
bones (ankle & heel),
metatarsals (sole) and
phalanges (toes)
Joints:
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These are a.k.a. articulations.
This is where 2 or more bones come together.
There are 3 types of joints:
 Fibrous
 Cartilaginous
 Synovial
Joints:
Fibrous Joints:
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Between bones that are
close together, united
by fibrous tissue.
Have limited
movement, if any.
Sometimes called
immovable joints.
Ex. Sutures of the skull
Cartilaginous Joints:
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Are shock absorbers
& equalize pressure;
united by
fibrocartilage.
Limited movement.
Ex. Vertebrate
http://www.google.com/imgres?
Synovial Joints:
Must have:
 Articulating cartilage
 Articular capsule (there is a membrane)
 Joint cavity (synovial fluid)
 Ligaments
 Many have bursae (flattened sacs of fluid) and
tendon sheaths (elongated bursae)
Types of Synovial Joints:
1.
2.
3.
Ball-and-socket joints allows the most
movement: rotational movement, side-to-side,
etc. Ex: shoulder or hip.
Condylar joints allow many motions but not
rotational. Ex: between phalanges &
metacarpels.
Plane joints allow sliding & twisting
movements. Ex: wrist or ankle.
Plane Joint:
Ball & Socket Joint:
Condylar Joint:
http://www.shockfamily.net/skelet
on/GLIDING.JPG
http://www.eorthopod.com/images/ContentIma
ges/hip/hip_arthroplasty/hip_arthroplasty_anat
01.jpg
http://pioneer.netserv.chula.ac.th/~bkritcha/figure/i
mages/condyloid.jpg
Types of Synovial Joints:
4.
5.
6.
Hinge joints allows planar movement only. Ex:
elbow.
Pivot joints allow rotational movement around a
central axis only. Ex: between radius & ulna.
Saddle joints allow a variety of movements. Ex:
between carpal & metacarpal of the thumb.
Hinge Joint:
http://www.eorthopod.com/images/ContentImag
es/elbow/elbow_anatomy/elbow_anatomy02a.jpg
Saddle Joint:
Pivot Joint:
http://www.shockfamily.net/skeleton/SADDLE.JP
G
http://www.dartmouth.edu/~anatomy/asse
ts/bones/elbow/elbow-supination.jpg
Look these up in text or online!
Know the following diseases/imbalances:
Rickets, fractures, herniated discs, scoliosis,
kyphosis & lordosis, bursitis, sprain, arthritis,
osteoarthritis, bone spurs, rheumatoid arthritis,
ankylosis, and gout, osteoporosis
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This slide show was developed by Dana Halloran,
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Cardinal Mooney High School, Sarasota, FL.
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Used with her personal permission,
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adapted and amended by Rosa Whiting,
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Manatee School for the Arts, Palmetto, FL.