At the completion of this unit, learners will be able to: 1. Define skeletal system 2. Discuss the structure, types and functions of bone 3. List the functions of the skeletal system 4. Identify the bones of axial & appendicular skeleton
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5. Describe the various markings on the surface of bones 6. Describe the bones of: The skull Vertebral column The rib cage or chest Pectoral girdle and upper extremity Pelvic girdle and lower extremity 7. Briefly discuss the difference between male & female pelvis.
2. • At the completion of this unit, learners will
be able to:
1. Define skeletal system
2. Discuss the structure, types and functions
of bone
3. List the functions of the skeletal system
4. Identify the bones of axial & appendicular
skeleton
Objectives
3. 5. Describe the various markings on the surface of bones.
6. Describe the bones of:
The skull
Vertebral column
The rib cage or chest
Pectoral girdle and upper extremity
Pelvic girdle and lower extremity
7. Briefly discuss the difference between male & female pelvis.
Objectives
4. The Human skeleton
• The framework of the body, consisting of
bones and other connective tissues, which
protects and supports the body tissues and
internal organs.
5.
6. The Skeletal System
Parts of the skeletal system
Bones (skeleton)
Joints
Cartilages
Ligaments (bone to bone)(tendon=bone to
muscle)
Divided into two divisions
Axial skeleton
Appendicular skeleton – limbs and girdle
7. Functions of Bones
Support of the body
Protection of soft organs
Movement due to attached skeletal
muscles
Storage of minerals and fats
Blood cell formation
8. Bones of the Human Body
The skeleton has 206 bones
Two basic types of bone tissue
Compact bone
Homogeneous
Spongy bone
Small needle-like
pieces of bone
Many open spaces
12. Classification of Bones
Long bones
Typically longer than wide
Have a shaft with heads at both ends
Contain mostly compact bone
• Examples: Femur, humerus
13. Gross Anatomy of a Long Bone
Diaphysis
Shaft
Composed of
compact bone
Epiphysis
Ends of the bone
Composed mostly of
spongy bone
14. Structures of a Long Bone
Periosteum
Outside covering of
the diaphysis
Fibrous connective
tissue membrane
Sharpey’s fibers
Secure periosteum to
underlying bone
Arteries
Supply bone cells
with nutrients
15.
16. Classification of Bones
Short bones
Generally cube-shape
Contain mostly spongy bone
Examples: Carpals, tarsals
17. Classification of Bones
Flat bones
Thin and flattened
Usually curved
Thin layers of compact bone around a layer
of spongy bone
Examples: Skull, ribs, sternum
18. Classification of Bones
Irregular bones
Irregular shape
Do not fit into other bone classification
categories
Example: Vertebrae and hip
19. Surface features of bones
Sites of attachments for muscles, tendons,
and ligaments
Passages for nerves and blood vessels
Categories of bone markings
Projections and processes – grow out from the
bone surface
Depressions or cavities – indentations
20. Types of Bone Cells
Osteocytes
Mature bone cells
Osteoblasts
Bone-forming cells
Osteoclasts
Bone-destroying cells
Break down bone matrix for remodeling and
release of calcium
Bone remodeling is a process by both
osteoblasts and osteoclasts
21. Changes in the Human Skeleton
In embryos, the skeleton is primarily hyaline
cartilage
During development, much of this cartilage
is replaced by bone
Cartilage remains in isolated areas
Bridge of the nose
Parts of ribs
Joints
22. Bone Growth
Epiphyseal plates allow for growth of
long bone during childhood
New cartilage is continuously formed
Older cartilage becomes ossified
Cartilage is broken down
Bone replaces cartilage
23.
24. Bone Fractures
A break in a bone
Types of bone fractures
Closed (simple) fracture – break that does not
penetrate the skin
Open (compound) fracture – broken bone
penetrates through the skin
Bone fractures are treated by reduction
and immobilization
Realignment of the bone
27. Axial skeleton supports and protects organs of head,
neck and trunk
Axial skeleton:
skull (cranium and facial bones)
hyoid bone (anchors tongue and muscles
associated with swallowing)
vertebral column (vertebrae and disks)
bony thorax (ribs and sternum)
Appendicular skeleton includes bones of limbs and
bones that anchor them to the axial skeleton
Appendicular skeleton:
pectoral girdle (clavicles and scapulae)
upper limbs (arms)
pelvic girdle (sacrum, coccyx)
lower limbs (legs)
Articulation- where joints meet, connect, and are formed.
28. 22 bones in skull
6 in middle ears
1 hyoid bone
26 in vertebral column
25 in thoracic cage
4 in pectoral girdle
60 in upper limbs
60 in lower limbs
2 in pelvic girdle
206 bones in all
29.
30. The Axial Skeleton
Forms the longitudinal part of the body
Divided into three parts
Skull
Vertebral column
Bony thorax
39. The Hyoid Bone
The only bone that
does not articulate
with another bone
Serves as a
moveable base for
the tongue
40. The Vertebral Column
Vertebrae
separated by
intervertebral discs
The spine has a
normal curvature
Each vertebrae is
given a name
according to its
location
46. Difference Between Male &
Female Pelvis
• The pelvis is one of the most useful skeletal
elements for differentiating between males
and females.
• Female pelves are larger and wider than
male pelves and have a rounder pelvic inlet.
• Male iliac crests are higher than females,
causing their false pelves to look taller and
narrower