1. End Show Slide 1 of 40 Copyright Pearson Prentice Hall 36–1 The Skeletal System

2. End Show 36–1 The Skeletal System Slide 2 of 40 Copyright Pearson Prentice Hall The Skeleton All organisms need structural support. Unicellular organisms have a cytoskeleton. Multicellular animals have either an exoskeleton (arthropods) or an endoskeleton (vertebrates). The human skeleton is composed of bone. Bones and other connective tissues, such as cartilage and ligaments, form the skeletal system.

3. End Show 36–1 The Skeletal System Slide 3 of 40 Copyright Pearson Prentice Hall The Skeleton The skeleton: supports the body. protects internal organs. provides for movement. stores mineral reserves. provides a site for blood cell formation.

4. End Show 36–1 The Skeletal System Slide 4 of 40 Copyright Pearson Prentice Hall Structure of Bones Bones are a solid network of living cells and protein fibers that are surrounded by deposits of calcium salts.

5. End Show 36–1 The Skeletal System Slide 5 of 40 Copyright Pearson Prentice Hall Structure of Bones Bone marrow Periosteum Spongy bone Compact bone Haversian canal Compact bone Spongy bone Periosteum Osteocyte Artery Vein

6. End Show 36–1 The Skeletal System Slide 6 of 40 Copyright Pearson Prentice Hall Structure of Bones Periosteum - tough outer layer of connective tissue Carry blood vessels & nerves to bone. Compact bone - thick layer of bone Haversian canals – holes that contain blood vessels and nerves. Spongy bone - has many spaces, but is still strong.

7. End Show 36–1 The Skeletal System Slide 7 of 40 Copyright Pearson Prentice Hall Structure of Bones Osteocytes are mature bone cells embedded in the bone matrix. Two Types: Osteoclasts break down bone. Osteoblasts produce bone.

8. End Show 36–1 The Skeletal System Slide 8 of 40 Copyright Pearson Prentice Hall Structure of Bones Bone marrow is a soft tissue inside the spongy bone There are two types: Yellow marrow is made up of fat cells. Red marrow produces all blood cells.

9. End Show 36–1 The Skeletal System Slide 9 of 40 Copyright Pearson Prentice Hall Development of Bones The skeleton of an embryo is composed of cartilage. Cartilage is a strong connective tissue that supports the body and is softer than bone. Ossification – process of bone formation by adding minerals around bone cells.

10. End Show 36–1 The Skeletal System Slide 10 of 40 Copyright Pearson Prentice Hall Types of Joints A place where one bone attaches to another bone is called a joint. Types: - immovable - slightly movable - freely movable

11. End Show 36–1 The Skeletal System Slide 11 of 40 Copyright Pearson Prentice Hall Types of Joints Immovable Joints Immovable joints, or fixed joints, allow no movement. The bones in the skull meet are examples of immovable joints.

12. End Show 36–1 The Skeletal System Slide 12 of 40 Copyright Pearson Prentice Hall Types of Joints Slightly Movable Joints These joints permit a small amount of restricted movement. Vertebrae Wrists & ankles Ribs

13. End Show 36–1 The Skeletal System Slide 13 of 40 Copyright Pearson Prentice Hall Types of Joints Freely Movable Joints These joints permit movement in one or more directions. Four common freely movable joints are: ball-and-socket joints hinge joints pivot joints saddle joints

14. End Show 36–1 The Skeletal System Slide 14 of 40 Copyright Pearson Prentice Hall Types of Joints Ball-and-socket joints permit movement in many directions.

15. End Show 36–1 The Skeletal System Slide 15 of 40 Copyright Pearson Prentice Hall Types of Joints Hinge joints permit back-and-forth motion.

16. End Show 36–1 The Skeletal System Slide 16 of 40 Copyright Pearson Prentice Hall Types of Joints Pivot joints allow one bone to rotate around another.

17. End Show 36–1 The Skeletal System Slide 17 of 40 Copyright Pearson Prentice Hall Types of Joints Saddle joints permit one bone to slide in two directions.

18. End Show 36–1 The Skeletal System Slide 18 of 40 Copyright Pearson Prentice Hall Structure of Joints In freely movable joints, cartilage covers the surfaces where two bones come together. Joints are also surrounded by a fibrous capsule that holds the bones together while still allowing them to move.

19. End Show 36–1 The Skeletal System Slide 19 of 40 Copyright Pearson Prentice Hall Structure of Joints Knee Joint Muscle Tendon Femur Patella Bursa Ligament Synovial fluid Cartilage Fat Fibula Tibia

20. End Show 36–1 The Skeletal System Slide 20 of 40 Copyright Pearson Prentice Hall Structure of Joints Ligaments hold bones together in joints and are attached to the periosteum. Synovial fluid forms a thin lubricating film over the surface of the joint. A bursa sac in a joint acts as a shock absorber.

21. End Show 36–1 The Skeletal System Slide 21 of 40 Copyright Pearson Prentice Hall Skeletal System Disorders Inflammation & excess fluid causes swelling, pain, heat, and redness. Inflammation of a bursa is called bursitis. Inflammation of the joint itself is called arthritis. Osteoporosis - loss of calcium in the bone. Fractures – broken bones.

22. End Show Slide 22 of 40 Copyright Pearson Prentice Hall 36–1 Red blood cells, some kinds of white blood cells, and platelets are produced by a.red marrow. b.cartilage. c.yellow marrow. d.osteocytes.

23. End Show Slide 23 of 40 Copyright Pearson Prentice Hall 36–1 Mature bone cells are called a.periosteum. b.osteocytes. c.bone marrow. d.Haversian canals.

24. End Show Slide 24 of 40 Copyright Pearson Prentice Hall 36–1 In freely movable joints, what covers the surfaces where the two bones come together? a.ligaments b.cartilage c.bursae d.tendons

25. End Show Slide 25 of 40 Copyright Pearson Prentice Hall 36–1 During ossification, cartilage is replaced by a.bone. b.ligament. c.marrow. d.tendon.

26. End Show Slide 26 of 40 Copyright Pearson Prentice Hall 36–1 The shoulder joint is an example of a a.ball-and-socket joint. b.hinge joint. c.pivot joint. d.saddle joint.

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