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The Skeleton is the name given to
the collection off bones in the
body and the tissues that
connect them.
The skeleton has 5 major functions.
1. It protects our vital organs such as the brain,
the heart, and the lungs
2. It gives us structure. Without it we would just
be a blob of blood and tissue on the floor.
3. It allows us to move. Because our muscles are
attached to our bones, when our muscles
move, they move the bones.
Functions
4. It stores calcium. Which keeps bones and
teeth hard.
5. It makes Red and White blood cells
Skeleton Facts
• When you were born, your skeleton had close
to 350 bones
• By the time you become an adult, you will
only have around 206 bones
– This is because, as you grow, some of the bones
fuse together to form one bone such as the skull.
• Our bones are 5 times stronger than steel
Skeleton Facts
• The smallest bones in the body are found in
the ear. (3mm)
• The longest bone in the body is the femur
• Over half the body's bones are in the hands
and feet.
• As your bones grow, you get taller. Girls
usually stop growing around age 16, and boys
around age 18.
Organization of the Human Skeleton
• Your skeleton is made up
of two parts; the axial skeleton
and the appendicular
skeleton.
Green = Axial
Purple = Appendicular
Colour the axial and appendicular parts of the skeleton
• Axial skeleton protects
the organs of your body
• Appendicular skeleton
allows movement
The Axial Skeleton
• Skull 29
• vertebral column 24
• ribs (12 pairs) 24
• Sternum 1
• Sacrum 1
• Coccyx 1
• Total 80
Green Area
The Appendicular Skeleton
• pectoral girdles (2 x 2) 4
• Arms (3 x 2) 6
• Wrists ( 8 x 2) 16
• hands (19 x 2) 38
• pelvis 2
• legs (4 x 2) 8
• ankles (7 x 2) 14
• feet (19 x 2) 38
• total 126
Purple Area
There are Four Main types of bone
1. Flat: like those found in the skull; provide
protection for soft tissues and points for muscle
attachment
2. Long: found in the arms and legs; provide
strength and support
3. Short: found in the wrists and ankles; provide
flexibility
4. Irregular: backbone, middle ear; have shapes
related to a specialized function
Bones
• Bones get their
strength and
rigidity from hard
deposits of
minerals such as
calcium and
phosphate.
• Bones are strong
but light because
they are hollow
and filled with a
substance called
Bone Marrow.
Bone Marrow
• is a spongy, fatty tissue that houses stem cells. These cells
•can transform themselves into platelets,
white or red blood cells that are needed
for immunity and circulation.
• Red marrow is found in some flat bones
(hip, skull, vertebrae and rib bones)
•Yellow marrow is a fat tissue storage site
in the middle of some longer bones.