230 likes | 482 Views
V. Skeleton. A. Skeleton Functions. Provides support and shape Internal framework determines body’s shape . Protects your organs (Axial Skeleton) Skull - the brain Rib cage - the heart and lungs Vertebrae - the spinal cord. Enables movement (Appendicular Skeleton)
E N D
A. Skeleton Functions • Provides support and shape • Internal framework • determines body’s shape • . • Protects your organs (Axial Skeleton) • Skull - the brain • Rib cage - the heart and lungs • Vertebrae - the spinal cord
Enables movement (Appendicular Skeleton) • Sites for muscle attachment • Pull of muscles makes movement possible • Produces blood cells • In the red bone marrow • Stores fat and minerals • Fat stored in yellow marrow • Calcium and phosphate stored in a rigid matrix
B. Skeleton Structure • Bones • 206 bones • Living tissue with blood vessels and nerves • Endoskeleton (inside the body) • . • Ligaments • Tough, flexible connective tissue • Holds bones together • Allows or prevents movement • . • Cartilage • Strong, flexible, smooth connective tissue • Cushions ends of bones • Allows smooth movement • .
C. Bone composition • Compact bone tissue • Dense • Rigid and hard • Forms around blood capillaries that feed the bone • . • Spongy bone tissue • Lacy open spaces • Provides strength and support • Found in long bones (arms and legs) • Sometimes contains red marrow
Mineral cycle – Growth and repair • Osteoblasts (bone cells) build calcium and other minerals into a matrix of bone • process is called ossification • Osteoclasts (bone cells) break down bone and deposit the calcium back into the blood (to build new bone) • Connective tissue • Collagen (a protein) makes bones flexible and durable • is woven into the matrix with the minerals • Marrow • Soft tissue inside of bones • Red Marrow • Produce red and white blood cells • Yellow Marrow • Stores fat
D. Bone Growth • Fetus – most bones start as cartilage • Cartilage replaced by bone as baby grows • Osteocytes (bone cells) move into cartilage and change it into bone • Cartilage in growth plates continues to produce bone as child grows • Directed by hormones • Growth finished at age 25-30 • Hardens completely • Can repair self if broken
E. Bone Connection - Joints • Joints • Allow movement or restrict movement • Connected by ligaments • Cushioned by cartilage • Fuse in skull (as a baby grows) • Types of joints • Ball and socket • Allows rotation • Example: shoulders and hips
Gliding joints • Allows flexibility in many directions • Example: Wrist and ankles • Hinge joints • Allows back and forth movement (like door hinge) • Example: knees and elbows • Pivot joints • Bones rotate and move slightly up and down • Example: vertebrae
Broken Wrist
F. Injuries and Disorders • Fractures • Impact breaks bone • Usually heals in 6-8 weeks • Sprains • Injury to ligament – stretching joint too far • Tissues tear • Swollen and painful to move • Common sports injury
Osteoporosis • Disease that causes bone tissue to become thin and weak • Weak bones break easily • Older adults who did not get enough calcium before they were 30 • Arthritis • Disease causes joints to swell, stiffen and become painful and misshapen • Treated with drugs that reduce swelling
VI. Muscles A. Function of Muscles • Pump blood through body • Stability and movement • Move material inside the body • Blood in arteries and veins • Digestion system
B. Three Types of Muscles • Three types of muscles • Skeletal • Voluntary – able to control movements • Contractions pull bones together • Most work in pairs around a joint - one contracts, the other relaxes • Flexor bends a joint • Extender straightens a joint • Example: bicep (flexor) and tricep (extender)
Smooth Muscle • Involuntary – not able to control • Internal organs and blood vessels • Moves materials through the body • Arteries and veins (blood) • Digestive system (food and waste) • Cardiac Muscle • Tissue that makes up the heart • Never gets tired – contains lots of mitochondria • Contractions push blood out of the heart
C. Injuries and disorders • Muscle strains and tears • Injury if overstretched or torn • Occurs if muscles are not warmed or stretched properly • Muscle tissue swells and is painful • Needs rest to heal • Muscular dystrophy • Hereditary disease that causes skeletal muscle to become weaker over time • Affects how muscle proteins form • Poor balance and difficulty walking
Tendinitis • Inflammation of tendons that connect muscle to bone • Can be torn if overused • Needs rest to heal • May be treated with medicines that reduce inflammation
D. Benefits of Exercise • Increase strength, endurance and flexibility • Keeps heart, lungs and bones healthy • Reduces stress and helps with sleep