11/25/2020
The skeletal system, which is made up of numerous bones, is the rigid
framework of the human body. Functions of bones:
• It gives support and shape to the body.
Bone Tissue • It protects vital organs such as the brain, spinal cord, and heart.
Zehra Güçhan Topcu, Assist. Prof. • It assists in movement by providing a rigid structure for muscle attachment
and leverage.
• The skeletal system also manufactures blood cells in various locations. The
main sites of blood formation are the ilium, vertebra, sternum, and ribs.
This formation occurs mostly in flat bones.
• Calcium and other mineral salts are stored throughout all osseous tissue of
the skeletal system.
Types of Skeleton
• The bones of the body are grouped into two main categories: axial
and appendicular.
• The axial skeleton forms the upright part of the body. It consists of
approximately 80 bones of the head, thorax, and trunk.
• The appendicular skeleton attaches to the axial skeleton and contains
the 126 bones of the extremities.
There are 206 bones in the body. Individuals may have additional
sesamoid bones, such as in the flexor tendons of the great toe and of
the thumb.
, 11/25/2020
Bones
Spongy (trabecular) bone Compact (cortical) bone
• These bones have trabecules • These bones create external
• Bone is made up of one‐third organic(living) material and two‐thirds regions of bones.
inorganic (nonliving) material. The organic material gives the bone which cross eachother.
elasticity, whereas the inorganic material provides hardness and strength, • They have high porosity. • They have vasculary channels
which makes bone opaque on an x‐ray. connected.
• They absorb energy.
• Compact bone makes up a hard, dense outer shell. It always completely • They give strength and
covers bone and tends to be thick along the shaft and thin at the ends of hardness.
long bones. It is also thick in the plates of the flat bones of the skull.
• Cancellous bone is the porous and spongy inside portion called the
trabeculae, which means “little beams” in Latin. They are arranged in a
pattern that resists local stresses and strains. These trabeculae tend to be
filled with marrow and make the bone lighter. Cancellous bone makes up
most of the articular ends of bones.
• The periosteum is a thin membrane that covers the
outer surface of all bones, except the articular
surfaces that are covered with hyaline cartilage. It
has two layers.
– Dense fibrous membrane covering the surfaces
of bones, consisting of an outer fibrous
layer and an inner cellular layer (cambium).
– The periosteum contains nerve and blood
vessels that are important in providing
nourishment, promoting growth in diameter of
immature bone, and repairing the bone. It also
serves as an attachment point for tendons and
ligaments.
• The endosteum (plural endostea) is a thin vascular
membrane of connective tissue that lines the inner
surface of the bony tissue that forms the medullary
cavity of long bones.
, 11/25/2020
Types of bones TYPES OF BONES
• Long bones
• Short bones
• Flat bones
• Irregüler bones
• Sesamoid bones
• Long bones are so named because their length is greater than their
width.
• Long bones are basically tubular shaped with a shaft (diaphysis) and
two bulbous ends (epiphysis). The wide part of the shaft nearest the
epiphysis is called the metaphysis. The diaphysis consists of compact
bone surrounding the marrow cavity. The metaphysis and epiphysis
consist of cancellous bone covered by a thin layer of compact bone.
Over the articular surfaces of the epiphysis is a thin layer of hyaline
cartilage.
The skeletal system, which is made up of numerous bones, is the rigid
framework of the human body. Functions of bones:
• It gives support and shape to the body.
Bone Tissue • It protects vital organs such as the brain, spinal cord, and heart.
Zehra Güçhan Topcu, Assist. Prof. • It assists in movement by providing a rigid structure for muscle attachment
and leverage.
• The skeletal system also manufactures blood cells in various locations. The
main sites of blood formation are the ilium, vertebra, sternum, and ribs.
This formation occurs mostly in flat bones.
• Calcium and other mineral salts are stored throughout all osseous tissue of
the skeletal system.
Types of Skeleton
• The bones of the body are grouped into two main categories: axial
and appendicular.
• The axial skeleton forms the upright part of the body. It consists of
approximately 80 bones of the head, thorax, and trunk.
• The appendicular skeleton attaches to the axial skeleton and contains
the 126 bones of the extremities.
There are 206 bones in the body. Individuals may have additional
sesamoid bones, such as in the flexor tendons of the great toe and of
the thumb.
, 11/25/2020
Bones
Spongy (trabecular) bone Compact (cortical) bone
• These bones have trabecules • These bones create external
• Bone is made up of one‐third organic(living) material and two‐thirds regions of bones.
inorganic (nonliving) material. The organic material gives the bone which cross eachother.
elasticity, whereas the inorganic material provides hardness and strength, • They have high porosity. • They have vasculary channels
which makes bone opaque on an x‐ray. connected.
• They absorb energy.
• Compact bone makes up a hard, dense outer shell. It always completely • They give strength and
covers bone and tends to be thick along the shaft and thin at the ends of hardness.
long bones. It is also thick in the plates of the flat bones of the skull.
• Cancellous bone is the porous and spongy inside portion called the
trabeculae, which means “little beams” in Latin. They are arranged in a
pattern that resists local stresses and strains. These trabeculae tend to be
filled with marrow and make the bone lighter. Cancellous bone makes up
most of the articular ends of bones.
• The periosteum is a thin membrane that covers the
outer surface of all bones, except the articular
surfaces that are covered with hyaline cartilage. It
has two layers.
– Dense fibrous membrane covering the surfaces
of bones, consisting of an outer fibrous
layer and an inner cellular layer (cambium).
– The periosteum contains nerve and blood
vessels that are important in providing
nourishment, promoting growth in diameter of
immature bone, and repairing the bone. It also
serves as an attachment point for tendons and
ligaments.
• The endosteum (plural endostea) is a thin vascular
membrane of connective tissue that lines the inner
surface of the bony tissue that forms the medullary
cavity of long bones.
, 11/25/2020
Types of bones TYPES OF BONES
• Long bones
• Short bones
• Flat bones
• Irregüler bones
• Sesamoid bones
• Long bones are so named because their length is greater than their
width.
• Long bones are basically tubular shaped with a shaft (diaphysis) and
two bulbous ends (epiphysis). The wide part of the shaft nearest the
epiphysis is called the metaphysis. The diaphysis consists of compact
bone surrounding the marrow cavity. The metaphysis and epiphysis
consist of cancellous bone covered by a thin layer of compact bone.
Over the articular surfaces of the epiphysis is a thin layer of hyaline
cartilage.
