The Body’s The Body’s Support Support

Structure:Structure:

The SkeletonThe Skeleton

Functions of the Functions of the skeleton:skeleton:

Functions of the Functions of the skeleton:skeleton:

o Provides shape and supportProvides shape and supporto Enables you to moveEnables you to moveo Protects your internal organsProtects your internal organso Produces red blood cellsProduces red blood cellso Stores materials like calcium until Stores materials like calcium until

your body needs ityour body needs it

o Provides shape and supportProvides shape and supporto Enables you to moveEnables you to moveo Protects your internal organsProtects your internal organso Produces red blood cellsProduces red blood cellso Stores materials like calcium until Stores materials like calcium until

your body needs ityour body needs it

Bone Strength: Some FactsBone Strength: Some Facts Bones are strong because they are Bones are strong because they are

made of tightly packed minerals made of tightly packed minerals like like calciumcalcium and and phosphorusphosphorus but but also so lightweight-they only make also so lightweight-they only make up 20% of an adult’s body up 20% of an adult’s body weight.weight.

They can absorb more force They can absorb more force without breaking than granite without breaking than granite or concrete.or concrete.

Bone GrowthBone Growth

o Because bones are living Because bones are living tissue they grow as you do.tissue they grow as you do.

o The more you exercise, the The more you exercise, the stronger they grow.stronger they grow.

o Broken bones heal by Broken bones heal by growing new tissue.growing new tissue.

Bone Structure:Bone Structure: The outermost layer is a thin tough layer The outermost layer is a thin tough layer

called the outer membrane (or called the outer membrane (or periosteum).periosteum).

Next is a layer of hard compact bone.Next is a layer of hard compact bone. Inside this is a layer of spongy bone which Inside this is a layer of spongy bone which

makes it lightweight but strong (from the makes it lightweight but strong (from the minerals minerals phosphorus and calciumphosphorus and calcium).).

Finally, the innermost layer is marrow-red Finally, the innermost layer is marrow-red (produces red blood cells) or yellow (which (produces red blood cells) or yellow (which stores fat).stores fat).

Bone Formation:Bone Formation:Bone Formation:Bone Formation:Most of an infant’s skeleton is cartilage, a soft, flexible connective tissue.

This is replaced over time by bone, except for at the end of bones. This cartilage acts as a cushion between joints.

Most of an infant’s skeleton is cartilage, a soft, flexible connective tissue.

This is replaced over time by bone, except for at the end of bones. This cartilage acts as a cushion between joints.

JointsJointsJointsJoints

o Joints are places where two bones Joints are places where two bones are joined together or meet.are joined together or meet.

o2 types: 2 types: immovable jointsimmovable joints (which (which don’t allow movement) like your don’t allow movement) like your skull) or skull) or moveable jointsmoveable joints which which allow movement (like your elbow).allow movement (like your elbow).

o4 kinds of moveable joints:4 kinds of moveable joints: HingeHinge (elbow); (elbow); Ball & SocketBall & Socket (hip) ; (hip) ; GlidingGliding (ankle); and (ankle); and PivotPivot (neck). (neck).

o Joints are places where two bones Joints are places where two bones are joined together or meet.are joined together or meet.

o2 types: 2 types: immovable jointsimmovable joints (which (which don’t allow movement) like your don’t allow movement) like your skull) or skull) or moveable jointsmoveable joints which which allow movement (like your elbow).allow movement (like your elbow).

o4 kinds of moveable joints:4 kinds of moveable joints: HingeHinge (elbow); (elbow); Ball & SocketBall & Socket (hip) ; (hip) ; GlidingGliding (ankle); and (ankle); and PivotPivot (neck). (neck).

Taking Care of BonesTaking Care of Bones Eat a balanced diet.Eat a balanced diet. Regular exercise causes bones Regular exercise causes bones

to grow strongerto grow stronger As people age, mineral loss can As people age, mineral loss can

lead to lead to osteoporosisosteoporosis, where , where bones become fragile. A diet bones become fragile. A diet rich in calcium can prevent this rich in calcium can prevent this disease.disease.

Marrow

Spongy bone

Spongy bone

Outer membrane

Outer membrane