3Functions:1. Gives Shape and support to the body2. Protect your internal organs3. Major muscles attach to bones to help you move4. Blood cells are formed in the bone. (The tissue called marrow)5. Store calcium and phosphorous compounds (calcium and phosphorous compounds make bones hard)
4Bone Major organs of the skeletal system Adult skeleton composed of 206 bonesStore mineralsIn certain bones, bone marrow produces blood cellsPicture: Ulna and radius bones in the forearm
6Periosteum :thin tough layer that covers all the bones, except the part of the bone that is in the joint. Blood vessels in the pariosteum carry the nutrients to the bone and cell that repair and cause growth are here.
7Compact bone:right under the periostreum this layer is the hard strong part. This layer gives bones strength contains deposits of calcium phosphate.
8Spongy Bone:is locate at the end of the long bones like those in your arms and legs. This part of the bone has lots of open spaces which keeps the bones light weight.
9Cavities:are the center of the long bones and contain the marrowMarrow:some marrow is red some yellow. Red marrow produced red blood (2 to 3 million per second) cells, yellow marrow is made up of fat.
10Connective Tissue Ligament Tendon Connects bone to bone Connects skeletal muscle to boneSkeletal musclePicture (Left): Ligament in the anklePicture (Right): Achilles TendonTendonBone
11Cartilage: soft and flexible tissue that provides padding in between bones.
22Types of Muscle Movement Involuntary- Automatically move without you knowing.Voluntary- You control the movements.22
23Types of MusclesSmooth Muscles- Which include the muscles of internal organs and blood vessels. These muscles move involuntary.Cardiac Muscle- Found only in the heart and also involuntary.Skeletal Muscles- Are voluntary and help you move.23
24Smooth Muscle Digestive organs Makes up 7-8% of your muscles Involuntary
25Cardiac Muscles Only found in the heart. Involuntary. Makes up 3% of your muscles.By age 70 heart contracts 2.5 billion times (assume resting heart beat).
26Skeletal Muscles Makes up 90% of your muscles. Voluntary- These are the muscles that you can move.
27Types of InjuriesStrain- Muscle “pull” or “strain” - Tearing a muscle fiber(s), followed by bleeding or swelling of muscleMuscle Cramp - Prolonged contraction of muscle
28Muscles and Movement Muscles can only contract & relax. Muscle fibers line up and pull the tendon attached to the bone to cause movement.
29Muscle PairsMuscle fibers line up and pull the tendon attached to the bone to cause movement.Your muscles work in teams to move your body. As one group of muscles is contracting another group is relaxing An example of this is your Bicep and Tricep.
32SummaryExplain how the Nervous System, Skeletal System and Muscular System all work together to create movement.
33Systems Working Together Our brain sends a message (NS)The message travels down your spinal cord (NS)The motor neuron fires a message (MS)The muscle contracts (MS)The muscle shortens pulling on the tendon (MS and SS)The bone connected to the tendon moves (SS)