Skeletal System*Just in time for Halloween!

(next week)Mon. Oct. 25

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 body2) Protects

1) Internal organs like brain, heart and lungs

3) Muscles are attached to bones4) Blood cells are formed inside bones5) Storage for important substances like calcium and

phosphorus

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

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

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

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

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

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?

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