SKELETAL SYSTEM
Functions of the Skeletal System
•Bones are made of OSSEOUS TISSUE
•Support and Protection
•Body movement
•Blood cell formation (bone marrow) - hemopoiesis
•Storage of inorganic materials
(salt, calcium, potassium….)
ORGANIZATION
•About 206
bones
•2 Main
Divisions –
Axial &
Appendicular
Axial Skeleton
•
•Head, neck, trunk
•Skull
•Hyoid Bone
•Vertebral Column
•Thoracic Cage (ribs, 12 pairs)
•Sternum
Hyoid Bone
Appendicular Skeleton
• Limbs & Bones that connect to the
o Pectoral Girdle (shoulders)
o Pelvic Girdle (hips)
BONE STRUCTURE - Long Bone
1.Epiphysis
2.Diaphysis
3.Articular Cartilage
4.Periosteum
Inside the Long Bone
Medullary Cavity –
hollow chamber filled
with bone marrow
Red Marrow (blood)
Yellow Marrow (fat)
Endosteum
– lining of the medullary
Types of Bone Tissue
Compact (wall of the diaphysis)
Spongy (cancellous, epiphysis) - red marrow
Structure of a Long Bone
Figure 6.3a-c
* Assignment
– Coloring of a Long
Bone
Review the Structure of a
Long Bone
Matching quiz at
http://www.mhhe.com/biosci/a
p/holehaap/student/olc2/chap
07matching01.html
Microscopic Structure
MATRIX - where the bone cells live
OSTEOCYTES - mature bone cells, enclosed in
tiny chambers called LACUNAE
OSTEOCYTES form rings (LAMELLAE) around a
HAVERSIAN CANAL which houses blood vessels
Osteocytes are linked by CANALICULI
Haversian Canals are linked by VOLKMAN's
CANALS
Compact Bone
BONE
COLORING!
Test Yourself
Find the...
Haversian Canal
Volkman's Canal
Lamellae
Spongy Bone
Compact Bone
BONE DEVELOPMENT & GROWTH
1.Intramembranous bones – flat, skull
2. Endochondral bones – all other
ALL BONES START AS HYALINE
CARTILAGE, areas graduallly turn to bone
PRIMARY OSSIFICATION CENTER (shaft)
SECONDARY OSSIFICATION CENTER
Bone Development & Growth
EPIPHYSEAL
DISK (growth plate) is a
band of cartilage
between the epiphysis
and diaphysis
These areas increase
bone length as the cells
ossify
Cartilage becomes
OSTEOBLASTS become
OSTEOCYTES
RESORPTION
OSTEOCLASTS - dissolve bone tissue to
release minerals, process is called
RESORPTION
Bone Growth
Bone Growth
* Assignment - Coloring of the Aging Hand
Types of Joints (articulations)
1.Synarthrotic (not
moveable, aka sutures)
2.Amphiarthrotic
(slightly moveable,
vertebrae)
3.Diarthrotic (moveable
joint, aka synovial
joints)
Synovial fluid - fluid
within the joints that
helps to lubricate
Types of Joints
1.
2.
3.
4.
Ball and Socket
Hinge
Pivot
Saddle
BONES OF THE SKULL
1. Frontal 2. Parietal 3. Occipital 4. Temporal 5. Sphenoid 6. Maxilla 7. Mandible 8. Zygomatic -
TOPOGRAPHY OF THE SKULL
Foramen - refers to any tiny opening, nerves
and blood vessels leave this opening to
supply the face
Mental Foramen
Suture - refers to any connection between large
bones (in fetal skulls, these are called fontanels)
Fissure - any wide gap between bones
Sutures
1. Coronal - between frontal and parietal
bones
2. Lambdoidal - between occipital and
parietal bones
3. Squamosal - between temporal and
parietal bones
4. Sagittal - between parietal bones
Bones of the Skull & Sutures
Foramen Magnum
* Assignment: Skull Labeling
Figure 6.10
Figure 6.10
The Rest of the Bones
Vertebrae
Neck = cervical
Middle Back = thoracic
Lower Back = lumbar
Thoracic Cage
Pectoral Girdle
Bones of the Arm
Ulna goes to
pinky (P-U)
Radius goes to
thumb
Wrist Bones
For test
Carpels
Metacarpals
Phalanges
*extra credit
opportunity
Name the carpals for extra credit
on test.
Pelvic Girdle
Bones of the Leg
Bones of the Ankle
For Test
Calcaneous
Tarsals
Metatarsals
Phalanges
Assignment –
Skeleton Labeling
Broken Bones
Upcoming Assignments
•The Skeleton Mystery - read about a “crime
•
•
•
scene” and reconstruct skeletons to identify
the remains
Watch a Bones Episode
Identify Bones on a real skeleton • Lab
Practical Test
Medical Imaging – learn how doctors view
bones and diagnose problems
TEST INFORMATION
•Test will cover everything in your notes and on the
slides presented in class
•Visit biologycorner.com for study aids
•A second test will occur that covers the lab portion
Abnormal Bone Conditions
• BONE SPURS: abnormal growth. Can occur on any bone
•
•
•
(e.g. heel).
OSTEOPOROSIS: Increased activity of osteoclasts cause
a break down bone, and the subsequent fewer minerals in
the extracellular matrix make it fragile. The spongy bone
especially becomes more porous.
Men get it as well as women. What’s the best way to
prevent osteoporosis? Exercise! What does exercise do?
Makes bones bigger.
The most common bone used for a bone graft is the iliac
bone of the hip.
Osteoporosis
Figure 6.15
Rheumatoid arthritis is an autoimmune disease
which causes joint stiffness and bone deformity
Source: http://www.thetimes.co.uk/tto/public/article3233439.ece
ABNORMALITIES OF THE SPINE
ABNORMALITIES OF THE SPINE
•SCOLIOSIS is a lateral curve in the spine
•KYPHOSIS is a hunchback curve
•LORDOSIS is a swayback in the lower region.
•ANKYLOSIS is severe arthritis in the spine and
the vertebrae fuse.
SCOLIOSIS
LORDOSIS
ANKYLOSIS
FUN FACTS ABOUT BONESBone is made of the
same type of minerals as limestone.
Babies are born with 300 bones, but by adulthood
we have only 206 in our bodies.
The giraffe has the same number of bones in its
neck as a human: seven in total.
The long horned ram can take a head butt at 25
mph. The human skull will fracture at 5mph.
•
•
•