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.

Tissue DescriptionCompact Bone The hard, dense outer

layer of bone

Spongy Bone Hard, but has many “holes” in it

Marrow Soft 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).

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.