Human Body Systems Unit

1. What is the job of the frame/walls of a building? 2. Why do you think we have bones? 3. What do you think would happen if we didn’t have bones? Catalyst

 Science Students will be able to describe the function, structure, and importance of our skeletal system. Mission(Objective):

 When a baby is born, not all of the bones in their skull have fused together so they have soft spots on their head called fontanel  Adults have 206 bones in their body

 The framework of bones and other tissues that supports the body

 Axial skeleton – consists of 80 bones in the head and trunk of the human body  Appendicular skeleton – composed of 126 bones that make up the appendages, or the parts that are joined to something larger, of the human body

 Axial skeleton – consists of 80 bones in the head and trunk of the human body

 Appendicular skeleton – composed of 126 bones that make up the appendages, or the parts that are joined to something larger, of the human body

 Shape and Support  Movement  Protection  Production  Storage

 Skeleton determines shape of your body just like the frame determines the shape of a building

 Bones form joints, which is a place where two bones come together  Joints allow bones to move in different ways

 Skull protects your brain  Rib cage protects heart, lungs, and other organs in the center of your body

 Bones produce (make) blood cells  The long bones in your arms and legs can be thought of as factories that make certain blood cells

 Bones store minerals until body needs them  These minerals include calcium and phosphorus, which are in many foods we eat

 The BONES are the organs of the body.  Made up of tissues. TissueDescription Compact BoneThe hard, dense outer layer of bone Spongy BoneHard, but has many “holes” in it MarrowSoft tissue with the spongy bone, makes blood cells

 Bones are classified by their shape: 1. Long- bones are longer than they are wide (arms, legs) 2. Short- usually square in shape, cube like (wrist, ankle) 3. Flat- flat, curved (skull, Sternum) 4. Irregular- odd shapes (vertebrae, pelvis)

 Osteocytes  Mature bone cells  Osteoblasts  Bone-forming cells  Osteoclasts  Bone-destroying cells  Break down bone matrix for remodeling and release of calcium  Bone remodeling is a process by both osteoblasts and osteoclasts

 In embryos, the skeleton is primarily hyaline cartilage  During development, much of this cartilage is replaced by bone  Cartilage remains in isolated areas  Bridge of the nose  Parts of ribs  Joints

 A break in a bone  Types of bone fractures  Closed (simple) fracture – break that does not penetrate the skin  Open (compound) fracture – broken bone penetrates through the skin  Greenstick- frays, hard to repair, breaks like a green twig  Bone fractures are treated by reduction and immobilization  Realignment of the bone

A joint, or articulation, is the place where two bones come together.  Fibrous- Immovable:connect bones, no movement. (skull and pelvis).  Cartilaginous- slightly movable, bones are attached by cartilage, a little movement (spine or ribs).ribs).  Synovial- freely movable, much more movement than cartilaginous joints. Cavities between bones are filled with synovial fluid. This fluid helps lubricate and protect the bones.

Hinge- A hinge joint allows extension and retraction of an appendage. (Elbow, Knee)

Ball and Socket- A ball and socket joint allows for radial movement in almost any direction. They are found in the hips and shoulders. (Hip, Shoulder)

Gliding- In a gliding or plane joint bones slide past each other. Mid-carpal and mid- tarsal joints are gliding joints. (Hands, Feet)

Saddle- This type of joint occurs when the touching surfaces of two bones have both concave and convex regions with the shapes of the two bones complementing one other and allowing a wide range of movement. (Thumb)

One bone can rotate around another.