4The skeleton is the body’s framework Bones: are classified by their shape:Long boneslonger than wideFound in the arms and legsShort bonesAs long as wideBones in the wrists and anklesFlat bonesThin and flat or slightly curvedRibcage and skullIrregular bonesShaped differently than long, short, or flatSpine and skull
5The skeleton is the body’s framework Provides the body’s shapeWorks with other systems to allow movementTwo main divisions:Axial skeleton (& Appendicular skeleton)central partIncludes skull, spinal column, ribsThe bones in the appendicular skeleton are attached to the axial skeleton
6What functions do vertebrae perform? They protect the spinal cord and support the cranium and other bones.How many bones are in the ankle and foot?26Which division of the skeleton includes the ankle and foot bones?Appendicular skeletonWhat is the only bone in the skull that can move?lower jaw
7Divisions of the Skeleton - Axial Skeleton Line straight down your back ~ axisSit, stand, twist…about your axisAxis ~ axial skeletonSupport and protectionTop: cranium – surrounds the brainCranium + bones in face (jaw, cheek…) = skullSkull connects to the spinal columnSpinal column (backbone): main portion of axial skeletonMade of vertebrae – bones stacked one on top of anotherRib bones and sternum
8Divisions of the Skeleton – Appendicular skeleton Bones that function to allow movementArms and legsUpper part:bones of the shoulders, arms, and handLower part:Bones in hips, legs, and feetBear all the body’s weight while standingLeg bones: strongest in your body
9Bones are living tissue Not solid – have spaces inside – lighter in weightMade of cells and mineralsContain blood vesselsMake, maintains, and break down bone tissueMinerals (ex: calcium) give bones structure and stiffnessBones:support and protect the bodyproduce and store blood cellsstore calcium for the body
10Bones are living tissue – two types of tissue Spongy boneStrongLightweightMineral part looks like a webSupports bones like beams support a buildingCan compress slightlyNear the end of long bones: absorb forcesRed bone marrow: produces blood cellsNew blood cells travel from marrow blood vessels in boneBlood brings nutrients to bone cells / carries away wasteCompact boneTough outer layer, surrounds spongy boneBasic supportive tissueDense, organized in layers - STRONG
11Why is the compact bone able to give the bone strength? It is dense.How does bone receive nourishment?Blood vessels bring in nutrients.Where are red blood cells formed?in the red bone marrow
12Joints connect parts of the skeletal system Joint: a place where two bones in the skeletal system meetallow the body to be flexibleThree types: immovable, slightly movable, and freely movable
13Immovable and Slightly Movable Joints Immovable jointlocks bones together like puzzle piecesSkull bones are connected by immovable jointsInside the cranium, the joints are called sutures (appear stitched - no space between)Slightly movable jointAble to flex a littleEx: ribs connected to sternum No space between bone, but bones connected by cartilage, so can move slightlyCartilage: tough but flexible connective tissueEx: outer ear, nose, cushions between vertebrae, shark!
14Freely Movable Joints Allow you to bend and move Most of the joints in your bodyWrist, knee, elbowBones are separated by a cavity containing fluidLigaments (tissue) hold bones together at movable jointsMaterials between bones (ex: fluid, cartilage) keeps them from rubbing togetherTendons (tissue) connect muscles to bones (but are not part of the joint)These all work together with muscles movement!
15Types of joints (6) – based on type of movement Hinge JointEx: elbow and kneeArm movement: angle between upper and lower arm decreases = angular movementBall-and-Socket JointEx: hip and shoulderPitchers, swimmers, quarterback, shotput…Shoulder can rotate in a circleRounded part of one bone fits into a cup-shaped part of anotherPivot JointEx: elbow, connecting the radius and ulnaRotational movement – rotate side to side (turn a doorknob)
17Types of joints (6) – based on type of movement Gliding JointEx: some joints in ankles and wrists, vertebraeSmall flat bones sliding or gliding over one anotherLimited movementSaddle JointONE ex: thumbLike a joystick – forward and backward, side to sideMore limited than ball-and-socket jointEllipsoid JointEx: in hands and feet at base of each finger and toeAllow bones to move like a hinge in different directions, but not rotateDifferent joints work together different movements!
20Each motion had a limited range of movement Each motion had a limited range of movement. The types and ranges of movement differed.Different joints allow rotational movements, angular movements, and gliding movements.
21Sometimes people get diseases that Real World ExampleSometimes people get diseases thatmake it painful to move their joints. Onesuch disease is bursitis. Bursas are fluidfilledsacs at the joints that cushionmovement. Occasionally, bursas becomeinflamed, making it harder for musclesand tendons to slide over bones.Movement is often painful. Bursitis canoccur when people repeat the samemotion over and over again. Tenniselbow is one form of bursitis. Bursitis canalso result from heavy pressure on a joint.Resting the joint and applying ice mayhelp reduce the inflammation.Teacher DemoDo the following demonstration to showhow important cartilage and synovialfluid, a kind of lubricant, are to makingjoints work smoothly. The cartilage andfluid reduce friction and wear on thebones. Ask students to watch as youpress and slide a wooden block that hasbeen sanded—not varnished or polished—along a flat wooden board. Youwill feel friction along the way. Next,wrap both the board and block in plasticbags. The plastic acts like cartilage as yourub the two pieces of wood together.Now, rub cooking oil on the plastic bagsand run the block along the board. Thecooking oil performs like synovial fluid inthe body does and makes it much easierto slide the two pieces of wood againsteach other.Ongoing AssessmentExplain how joints allow movement.Do the following demonstration to showhow important cartilage and synovialfluid, a kind of lubricant, are to makingjoints work smoothly. The cartilage andfluid reduce friction and wear on thebones. Ask students to watch as youpress and slide a wooden block that hasbeen sanded—not varnished or polished—along a flat wooden board. Youwill feel friction along the way. Next,wrap both the board and block in plasticbags. The plastic acts like cartilage as yourub the two pieces of wood together.Now, rub cooking oil on the plastic bagsand run the block along the board. Thecooking oil performs like synovial fluid inthe body does and makes it much easierto slide the two pieces of wood againsteach other.
22How does position affect support? PROCEDUREHold the bag in your hand and keep your arm straight. Move the bag up and down.Move the handles of the bag over your elbow. Again hold your arm straight and move the bag up and down.Move the bag to the upper part of your arm and repeat the procedure.WHAT DO YOU THINK?At which position was it easiest to move the bag?At which position did the bag move the farthest?nearest to the shoulderin the hand