The skeletal system is made up of bones, cartilage, ligaments, and joints. It has two divisions - the axial skeleton which includes the skull, vertebral column, and thorax, and the appendicular skeleton which includes the upper and lower limbs. The skeletal system performs many functions including movement, support, protection, blood cell production, and mineral storage. It contains over 200 bones that can be classified by shape and location in the body. Joints connect bones and allow different types of movement.

1. TheSkeletal
System:

2. THE SKELETAL SYSTEM
Parts of the skeletal
system
Bones (skeleton)
Joints
Cartilages
Ligaments

3. THE SKELETAL SYSTEM
Divided into two divisions
Axial skeleton
Appendicular skeleton –
limbs and girdle

4. FUNCTIONS
OF THE
SKELETAL
SYSTEM

5. 1. Movement: Skeletal
system provides points of
attachment for muscles.
Your legs and arms move
when the muscles pull on
the bones.

6. 2. Support: The backbone
is the main support center
for the upper body. It
holds your head up and
protects your spinal cord.

7. 3. Protection: The bones
of your skull protect your
brain. Your ribs protect
your lungs and heart from
injury.

8. 4. Makes Blood: Red and
white blood cells are
formed by tissue called
marrow, which is in the
center of the bone.

9. 5. Storage: Bones store
minerals, such as calcium
and phosphorus, for use
by the body

10. BONES OF THE HUMAN BODY
The skeleton has 206
bones
Two basic types of bone
tissue

11. BONES OF THE HUMAN BODY
Compact bone
Homogeneous
Spongy bone
Small needle-like pieces
of bone

12. MICROSCOPIC ANATOMY OF BONE

13. Bones areclassified by their
shape:
•long
•short
•flat
•irregular

14. Classification of Bones on the Basis of
Shape

15. Long bones
Typically longer than
wide
Have a shaft with heads
at both ends
Contain mostly compact
bone

16. GROSS ANATOMY OF A
LONG BONE
Diaphysis
Shaft
Composed of compact
bone

17. GROSS ANATOMY OF A
LONG BONE
Epiphysis
Ends of the bone
Composed mostly of
spongy bone

18. STRUCTURES OF A LONG
BONE
Periosteum
Outside covering of the
diaphysis
Fibrous connective tissue
membrane

19. Sharpey’s fibers
Secure periosteum to
underlying bone
Arteries
Supply bone cells with
nutrients

20. Sharpey’s fibers
Secure periosteum to
underlying bone
Arteries
Supply bone cells with
nutrients

21. CLASSIFICATION OF BONES
Short bones
Generally cube-shape
Contain mostly spongy
bone
Examples: Carpals,
tarsals

22. CLASSIFICATION OF BONES
Flat bones
Thin and flattened
Usually curved
Thin layers of compact
bone around a layer of
spongy bone

23. CLASSIFICATION OF BONES
Irregular bones
Irregular shape
Do not fit into other
bone classification
categories

24. TYPES OF BONE CELLS
Osteocytes
Mature bone cells
Osteoblasts
Bone-forming cells
Osteoclasts
Bone-destroying cells

25. Bone remodeling is a
process by both
osteoblasts and
osteoclasts

26. CHANGES IN THE HUMAN
SKELETON
In embryos, the skeleton
is primarily hyaline
cartilage
During development,
much of this cartilage is
replaced by bone

27. CHANGES IN THE HUMAN
SKELETON
Cartilage remains in
isolated areas
Bridge of the nose
Parts of ribs
Joints

28. BONE GROWTH
Epiphyseal plates allow
for growth of long bone
during childhood
New cartilage is
continuously formed

29. BONE GROWTH
Older cartilage becomes
ossified
Cartilage is broken down
Bone replaces cartilage

31. BONE FRACTURES
A break in a bone
Types of bone fractures
Closed (simple) fracture –
break that does not
penetrate the skin

32. BONE FRACTURES
Open (compound)
fracture – broken bone
penetrates through the
skin

33. COMMON TYPES OF FRACTURES

34. Stages in the Healing of a Bone Fracture

35. Axial skeletonsupports
and protects organs of
head,neck and trunk

36. Appendicular skeleton
includes bones of limbs
and bones that anchor
them to the axial skeleton

37. 22 bones in skull
6 in middle ears
1 hyoid bone
26 in vertebral column
25 in thoracic cage

38. 4 in pectoral girdle
60 in upper limbs
60 in lower limbs
2 in pelvic girdle
= 206 bones in all

40. THE AXIAL SKELETON
Forms the longitudinal
part of the body
Divided into three parts
-Skull -Bony thorax
-Vertebral column

41. THE AXIAL SKELETON

43. BONES OF THE SKULL

44. Allows for
growth

45. HUMAN SKULL, SUPERIOR VIEW

46. HUMAN SKULL, INFERIOR VIEW
Figure 5.9

47. PARANASAL SINUSES
Hollow portions of
bones surrounding the
nasal cavity

48. PARANASAL SINUSES
Hollow portions of
bones surrounding the
nasal cavity

49. THE HYOID BONE
The only bone that does
not articulate with another
bone
Serves as a moveable
base for the tongue

50. THE HYOID
BONE

51. THE VERTEBRAL COLUMN
 Vertebrae separated by
intervertebral discs
 The spine has a normal
curvature
 Each vertebrae is given a
name according to its
location

52. THE VERTEBRAL COLUMN
Vertebrae separated by
intervertebral discs
The spine has a normal
curvature

53. THE VERTEBRAL COLUMN
Each vertebrae is given a
name according to its
location

54. THE
VERTEBRAL
COLUMN

55. Vertebral column
7 cervial vertebrae
12 thoracic
5 lumbar
1 sacrum (5 fused
1 coccyx (4 fused)

57. STRUCTURE OF A TYPICAL
VERTEBRAE

58. True ribs are directly
attached to the sternum
(1st 7 pairs)
Three false ribs are joined
to the 7th rib two pairs of
floating ribs

60. Joints
•Fibrous joints connect
bones without allowing any
movement. The bones of
your skull and pelvis are
held together by fibrous
joints.

61. Joints
•Cartilaginous joints are
joints in which the bones
are attached by cartilage.
These joints allow for only
a little movement, such as
in the spine or ribs.

62. Joints
•Synovial joints allow for
much more movement
than cartilaginous joints.
Cavities between bones in
synovial joints are filled
with synovial fluid.

63. • A joint, or articulation,
is the place where two
bones come together.
• There are three typesof
joints classified by the
amount of movement
they allow:

64. Types of Joints
Hinge- A hinge joint allows
extension and retraction
of an appendage. (Elbow,
Knee)

65. Types of JointsHinge- A hinge joint allows extension and retraction of
an appendage. (Elbow, Knee)

66. Ball and Socket- A ball
and socket joint allows for
radial movement in almost
any direction. They are
found in the hips and
shoulders. (Hip, Shoulder)

67. Ball and Socket- A ball
and socket joint allows for
radial movement in almost
any direction. They are
found in the hips and
shoulders. (Hip, Shoulder)

68. Pivot joints enable
rotating the forearm at
the elbow and turning the
head from side to side.

70. Gliding- In a gliding or
plane joint bones slide
past each other. Mid-
carpal and mid- tarsal
joints are gliding joints.
(Hands, Feet)

71. Gliding- In a gliding or
plane joint bones slide
past each other. Mid-
carpal and mid- tarsal
joints are gliding joints.
(Hands, Feet)

72. WHAT IS THE
STRUCTURE OF
BONE?

73. Bones are complex living
structures that undergo
growth and development.

74. Beneath the outer
membrane is a layer of
compact bone (hard and
dense, but not solid – it is
filled with holes and has
small canals for blood
vessels and nerves).

75. Inside the compact bone is
a layer of spongy bone.
It has many small spaces,
is light weight, but strong.
Spongy bone is also found
at the ends of bones.

76. –In the spaces of many
bones there is a soft
connective tissue called
marrow.
–Two types of Marrow:
►Red
►Yellow

77. –Red Marrow produces
most of the body’s
blood cells.
–Yellow Marrow stores
fat that can serve as
an energy reserve.

78. The structure of bones
make it both strong and
light weight.
20 % of an adults body
weight is bone.

79. Bone is made up of 2
minerals:
►Calcium
►Phosphorus

80. HOW DO BONES DEVELOP?
–As an infant, most of
your skeleton is
cartilage.
–Cartilage is a strong
flexible tissue.

81. CLAVICLE OR COLLARBONE
►The clavicle, or collar
bone, holds the shoulder
joint away from the rest of
the upper body and is only
as thick as your little finger.

83. ►The scapula is located
on the back side of the
ribcage and helps provide
part of the shoulder joint
and movement for the
arms.

84. 1) The cervical region
(neck bones)
2) The thorasic region
(what the ribs attach
to)
3) The lumbar region
(the lower part of the
back)

85. 1) The cervical region (neck bones)
2) The thorasic region (what the ribs attach to)
3) The lumbar region (the lower part of the back)

86. COCCYX AND SACRUM

87. HUMERUS
(UPPER
ARM
BONE)

88. RADIUS AND ULNA

89. CARPALS OR (WRIST BONES)

90. METACARPALS (TOP OF HANDS)

91. PHALANGES (LITTLE FINGERS)

92. RIB CAGE

93. STERNUM (BREASTBONE)

94. PELVIS

95. FEMUR
(LARGEST BONE IN THE BODY)

96. THE TIBIA AND FIBULA

97. TARSALS

98. METATARSALS

99. PHALANGES

100. WHAT ARE JOINTS?
• A joint is a place where
two bones come
together.
• Joints allow the bones
to move in different
ways.
• Two types of joints:
• Immovable
• Movable

101. WHAT ARE IMMOVABLE JOINTS?
• A joint that allows
little or no
movement

102. WHAT ARE MOVABLE JOINTS?
• Most of the joint are
movable joints.
• Allow the body to move in
a wide range of
movements.
• Bones in movable joints
are held together by
strong connective tissue
called ligaments.
• Four types of movable
joints:
• Hinge
• Ball-and-socket
• Pivot