The Skeletal System BONES

Functions: 1. Mechanical Support – bones are the framework for the attachment of muscles and other tissues Movement – bones enable the body movements by acting as levers and points of attachment for muscles so they pull on the bone when the muscle contracts

Function: 2. Protection The skull and ribcage protect vital organs from injury Bones protect marrow (the inside of the bone) which creates new blood cells

Function: 3. Metabolic (Production) Mineral storage – bones store essential minerals, like calcium, which are released throughout the body when needed Blood cell production – Blood cell formation occurs in the red marrow found within the cavities of certain bones Red bone marrow produces red blood cells and white blood cells Energy storage – fats stored in the yellow marrow serve as energy storage Found in long bones (arm and leg bones)

What are bones? Bones are made up of living cells and store minerals. If bones break, they can heal

Bones have jobs? The skull This is an important bone because it protects your brain, which is very soft. It also gives your face its’ shape. The side view of the skull

Jobs The Spinal Column also known as the backbone It is attached to your skull and made up of small bones stacked on top of each other. It supports your head and body and has muscles and nerves that run along it.

Jobs: The Ribs There are 12 pairs of flat bones to form a cage. It protects your heart and lungs, and involved with breathing (like we just learned!)

Jobs: Arm and Legs Each arm has one bone that runs from your shoulder to your elbow (the humorous), and two bones from your elbow to your wrist (radius and ulna).

Jobs: Your leg bones begin at your hip, and run down to your knee (the femur) and then there are two bones that make up your lower leg (the tibia and fibula)

How do bones move? Your bones would not be able to move without joints. A joint is formed where two bones meet. Some joints allow a lot of movement, like your knee joint, and others only allow a little or no movement, like your skull. Ligaments are strong, elastic fibers that stretch and tighten like rubber bands. The hold the bones of the joints together. Cartilage is a layer of gel material that reduces friction between your bones at the joints. It acts like a cushion for your joints when you jump.

Example of a joint: Knee

Critical Challenge Time!