THE THE SKELETAL SKELETAL

SYSTEMSYSTEM

What the Skeletal System What the Skeletal System Does...Does...

5 major functions5 major functions:: Shape and supportShape and support MovementMovement Protects your organsProtects your organs Produces blood cellsProduces blood cells Stores mineralsStores minerals

Shape and SupportShape and Support

Backbone (or Backbone (or vertebral column) vertebral column) is the center of the is the center of the skeleton.skeleton.

VertebraeVertebrae: The : The small bones that small bones that make up the make up the backbone.backbone.

MovementMovement Bones are associated with muscles.Bones are associated with muscles. Muscles pull on the bones to make the Muscles pull on the bones to make the

body move. body move.

ProtectionProtection Bones protect your organs.Bones protect your organs. Skull protects brain.Skull protects brain. Breastbone and ribs protect heart and Breastbone and ribs protect heart and

lungs.lungs.

Blood ProductionBlood Production Bones are like factories that Bones are like factories that

produce blood cells.produce blood cells.

Mineral StorageMineral Storage Bones store Bones store calciumcalcium

and and phosphorousphosphorous.. Bones release Bones release

minerals into the minerals into the blood when the body blood when the body needs them. needs them.

Joints of the SkeletonJoints of the Skeleton

JointJoint: A place in the body where 2 : A place in the body where 2 bones come together. bones come together.

Joints allow bones to move in Joints allow bones to move in different ways.different ways.

2 types of joints: 2 types of joints: immovableimmovable and and moveablemoveable

Immovable JointsImmovable Joints Joints that connect Joints that connect

bones in a way bones in a way that allows little or that allows little or no movement.no movement.

Bones of the skull Bones of the skull are held together are held together by immovable by immovable joints.joints.

Moveable JointsMoveable Joints Allow body to make Allow body to make

movements.movements. LigamentsLigaments: Strong : Strong

connective tissues connective tissues that hold moveable that hold moveable joints together. joints together.

CartilageCartilage: A 2nd : A 2nd type of connective type of connective tissue.tissue.

4 Types of Moveable Joints4 Types of Moveable Joints

Hinge jointHinge joint Ball and socket jointBall and socket joint Pivot jointPivot joint Gliding jointGliding joint

Hinge JointHinge Joint

A hinge joint allows A hinge joint allows forward or backward forward or backward motion. Your knee is motion. Your knee is a hinge joint that a hinge joint that allows you to bend allows you to bend and straighten your and straighten your leg. Your elbow is leg. Your elbow is also a hinge joint. also a hinge joint.

Ball and Socket JointBall and Socket Joint

Ball and socket joints Ball and socket joints allow the greatest allow the greatest range of motion. range of motion. The ball and socket The ball and socket joint in your shoulder joint in your shoulder allows you to swing allows you to swing your arm freely in a your arm freely in a circle. Your hips also circle. Your hips also have ball and socket have ball and socket joints.joints.

Pivot JointPivot Joint

A pivot joint A pivot joint allows one bone allows one bone to rotate around to rotate around another. The another. The pivot joint in your pivot joint in your neck allows you neck allows you to turn your head to turn your head from side to side. from side to side.

Gliding JointGliding Joint

A gliding joint A gliding joint allows one bone to allows one bone to slide over another. slide over another. The gliding joint in The gliding joint in your wrist or ankle your wrist or ankle enables you to enables you to bend and flex as bend and flex as well as make well as make limited side to side limited side to side motions. motions.

CartilageCartilage Covers the ends of bones and Covers the ends of bones and

keeps them from rubbing.keeps them from rubbing.

Bone StructureBone Structure

Bones are complex living structures Bones are complex living structures that undergo growth and that undergo growth and development. development.

Compact bone-Compact bone- Hard and dense, Hard and dense, but not solid. but not solid.

Spongy bone-Spongy bone- Like Like a sponge with a sponge with many small spaces many small spaces within it. within it.

Marrow-Marrow- Soft Soft connective tissue connective tissue that fills the spaces that fills the spaces in your bones. (2 in your bones. (2 types- red and types- red and yellow) yellow)

TYPES OF BONE MARROWTYPES OF BONE MARROW Red Marrow- Produces most of the Red Marrow- Produces most of the

body’s blood cells. As a child, body’s blood cells. As a child, most of your bones contain red most of your bones contain red marrow. marrow.

Yellow Marrow- Stores fat. As a Yellow Marrow- Stores fat. As a adult, most of your bones contain adult, most of your bones contain 50 %yellow marrow and 50 % red 50 %yellow marrow and 50 % red marrow. marrow.

Bone StrengthBone Strength

The structure of bones make them The structure of bones make them both strong and lightweight. both strong and lightweight.

Bones can absorb more force than Bones can absorb more force than concrete or granite rock. concrete or granite rock.

20 percent of an adults body weight 20 percent of an adults body weight is bone. is bone.

Bone GrowthBone Growth Bones are alive! They contain cells Bones are alive! They contain cells

and tissues, such as blood and and tissues, such as blood and nerves. nerves.

Bone DevelopmentBone Development As an infant, much of As an infant, much of

your skeleton is your skeleton is cartilage. Over time, cartilage. Over time, most of your cartilage is most of your cartilage is replaced with hard bone replaced with hard bone tissue. tissue.

Taking Care of Your BonesTaking Care of Your Bones A combination of a balanced diet A combination of a balanced diet

and regular exercise are important and regular exercise are important for a lifetime of healthy bones. for a lifetime of healthy bones.

How Does Physical Activity How Does Physical Activity Help Build Healthy Bones?Help Build Healthy Bones?

Bones are living tissue. Bones are living tissue. Weight-Weight-bearing physical activity causes bearing physical activity causes new bone tissue to form, and new bone tissue to form, and this makes bones stronger. this makes bones stronger. This This kind of physical activity also makes kind of physical activity also makes muscles stronger. Bones and muscles stronger. Bones and muscles both become stronger when muscles both become stronger when muscles push and tug against bones muscles push and tug against bones during physical activity.during physical activity.

Exercise ExamplesExercise ExamplesWeight-bearing physical activity keeps you on your feet Weight-bearing physical activity keeps you on your feet so that your legs carry your body weight. Some so that your legs carry your body weight. Some examples of examples of weight-bearing physical activities weight-bearing physical activities include:include: Walking, jogging, or runningWalking, jogging, or running Playing tennis or racquetballPlaying tennis or racquetball Playing field hockeyPlaying field hockey Climbing stairsClimbing stairs Jumping rope and other types of jumpingJumping rope and other types of jumping Playing basketballPlaying basketball DancingDancing HikingHiking Playing soccerPlaying soccer Lifting weights Lifting weights

OsteoporosisOsteoporosis A condition in which the body’s A condition in which the body’s

bones become weak and break bones become weak and break easily (not enough calcium). easily (not enough calcium).