This document provides an overview of the skeletal system. It notes that the skeletal system provides structure and support to the body, protects internal organs, allows for muscle attachment, and stores important substances. The skeletal system includes around 200 bones separated into those in the arms/legs and those in the skull, spine, and ribs. Bones are living organs made of layers of tissue that come in different shapes and sizes depending on their function. Bones meet at joints and are covered in cartilage, which helps with movement and absorbing shock. The document discusses bone fractures, the bone repair process, and ways to keep bones healthy like drinking milk, exercising, and preventing osteoporosis. An activity is described to show bones are strongest in cylindrical shapes like

1. Skeletal System
*Just in time for Halloween!
(next week)
Mon. Oct. 25

2. Why learn about the skeletal system?
• Framework for our body!
– Like the frame for a building,
it connects to, and holds up
the rest of the body
• Important functions (5):
1) Shape and support to body
2) Protects
1) Internal organs like brain, heart and lungs
3) Muscles are attached to bones
4) Blood cells are formed inside bones
5) Storage for important substances like calcium and
phosphorus

3. What parts are included in the skeletal
system?
• Human skeleton is separated into 2 parts:
1) Bones of arms and legs
2) Bones of skull, spine, ribs

4. Bones
• There are around 200
bones in the human body
• Bone is ALIVE! Bones are
dense organs made of
layers of tissue
• Many different sizes and
shapes, depending on the
function in human body
(Fig. 18-2, go to pg.495)
– All bones are not smooth:
some have bumps, holes,
rough spots, smooth spots

5. Bones continued…
• Where two or more
bones meet they form a
JOINT ex. elbow, knee
• Cartilage: Ends of bones
are covered in cartilage
– It is flexible and
important at joints to
help absorb shock
– Makes movement easier
• Ex: when you are playing
sports and jump around,
the cartilage absorbs the
shock in your knees

6. Broken bones
• Your bones are very strong, but even bones
may break: ex. falling off a bicycle, horse
• Breaking a bone is called a FRACTURE, and
there are many different types
• Blood cells move and create a clot between
the space where the break is. Bone cells are
then sent to this area and multiply to
eventually repair the break

7. How do we keep our bones healthy?
• Drink MILK!
– Milk contains calcium, which helps to make bones strong
– You have until you are about 19 years old to develop
strong bones
• Exercise
– Build your muscles to help support your bones
• When bones become weak: Osteoporosis
– As all people get older, their bones become less dense
– If someone has osteoporosis, their bones have become
weakened, and these can break more easily

8. Activity: What shape are our bones?
• Instructions: WITH YOUR GROUP, you will create different
shapes to see which are stronger (can hold a textbook/binder),
and relate this to the shape of our bones
1) Take half of your cardboard cards and tape to create a
rectangular column
2) Take the other half of your
cardboard cards and tape them to
create a cylindrical (round) column
3) Place a binder or textbook on top of each
column and observe which collapses first
4) Which is stronger?
What is the shape of our bones?
1 2