1. THE SKELETAL SYSTEM CH. 6 INTRODUCTION TO CHAPTER

2. ROOTS: arthr/o = joint cervic/o = neck chondr/i, chondr/o, chondr/io = cartilage cost/o = rib myel/o= bone marrow occipit/o = back of head oss/eo, oss/i, ost/e, ost/eo = bone sacr/o = sacrum spondyl/o = vertebra stern/o = sternum

3. WHY DO WE NEED A SKELETON? It provides a framework for the body and gives it ___________. It supports organs and ____________ them from injury. It provides a place for muscles, ligaments, and tendons of the body to ____________ to. It helps to make ________________ possible. It stores ______________. It provides a place for __________________.

4. WHAT IS BONE AND WHAT IS IT MADE OF? Bone is one of the types of ______________ tissue in the body. It is also called _____________ tissue. It is made up of water and mineral salts. ________________ is the formation of or conversion into bone or a bony substance (calcification is the deposition of calcium in a tissue).

5. WHAT IS BONE MADE OF? The outer surface is called _____________ BONE and is very dense. It is the thickest in the midshaft of a long bone to provide strength and prevent bending of the bone The inner layer is called ________________ BONE and is spongy and latticelike and is less dense than compact bone

6. WHAT IS BONE MADE OF? The SHAFT (____________) of the bone contains the _____________ CAVITY It is filled with YELLOW MARROW (fat storage) and RED MARROW (hematopoietic tissue) Yellow marrow replaces red marrow as an animal ages.

7. WHAT IS BONE MADE OF? ________________ covers the surface of bone and is a tough, vascular membrane. It is where tendons, ligaments, and muscles attach to the body. It has a nerve and blood supply. The inner layer of the periosteum contains ___________________ which are cells responsible for bone growth and repair.

8. WHAT IS BONE MADE OF ? The medullary cavity of bone has arteries and veins that enter and exit the cavity via the ___________ ____________ which are openings in the bone

9. HOW DO BONES GROW? They grow in LENGTH at the junction of the EPIPHYSIS and the DIAPHYSIS at the _____________ _________ (growth plate). It is also called the ___________. They grow in THICKNESS in the layers of the periosteum.

10. HOW DO BONES GROW? Bones are stimulated to grow via ___________ HORMONE (GH) which is produced by the ____________ gland. There is a teamwork between ______________ producing bony tissue and _______________ eating away bony tissue to prevent the bone from becoming too thick. This process slows as an animal ages.

11. SHAPES OF BONE ________ (femur, humerus) ________ (carpal bones) ________ (sternum, scapula) ____________ (vertebrae)

12. AXIAL & APPENDICULAR SKELETON AXIAL SKELETON: SKULL, HYOID BONE,VERTEBRAL COLUMN, RIBS, STERNUM APPENDICULAR SKELETON: BONES OF THE LIMBS

13. SKULL 2 major segments: Bones of the Cranium and Facial Bones PURPOSE: protects the brain and the sensory organs. The ONLY mobile bone is the ______________________ (lower jaw) The skull bones unite at the ____________.

14. SINUSES are located within the skull and are _______- filled cavities Sinuses are usually named for the skull bone that contains the sinus The nares open into 2 major air passages that end in the pharynx. The nasal passages are filled with very fine scrolls of bone called ___________________. These are covered in pink mucosa. Air is warmed, moistened, and filtered as it passes through the turbinates in the nose on the way to the lungs.

15. CRANIAL BONES FRONTAL BONES – form the forehead Horns are an extension of the frontal bone PARIETAL BONES – form upper part of each side of the skull TEMPORAL BONES – form the lower part of the sides of the skull. OCCIPITAL BONE – forms the back of the skull foramen magnum– opening at the base of the occipital bone that allows the spinal cord to pass from the skull to the spine

16. FACIAL BONES MAXILLA – bone that forms the upper jaw MANDIBLE – forms the lower jaw. Only movable bone in the skull maxilla mandible

17. HYOID APPARATUS – U shaped structure made up of both bone and cartilage. Suspends the tongue, larynx, and floor of the mouth

18. VERTEBRAL COLUMN (backbone) There are 5 types of vertebrae: ____________(C), ____________ (T), ______________ (L), ____________ (S), _______________ (Cy)

19. Each vertebrae has a body and an arch. Each vertebrae has a body and an arch. –Body – bears the weight –Arch – forms the canal that houses the spinal cord Intervertebral discs are between the bodiesIntervertebral discs are between the bodies -Made of cartilage and serve as shock absorbers-Made of cartilage and serve as shock absorbers

20. CERVICAL VERTEBRAE 1 st vertebrae: _______: supports the skull 2 nd vertebrae: _____: what the atlas rotates on

21. THORACIC VERTEBRAE Attach to ribs Thoracic Cage: composed of the thoracic vertebrae, ribs, costal cartilages, and sternum protects the vital organs of the chest and allows the lungs to expand and contract during respiration

22. RIBS PURPOSE: form the thoracic wall and protect the heart and lungs Flat, curved Each rib has bony and cartilagenous components The cartilagenous component is located ventrally They unite at the ___________________ junction

23. STERNUM BREASTBONE Located on ventral midline of chest Flat bones called STERNEBRAE that connect to each other via cartilage Most cranial bone is the __________________ Most caudal bone is the __________________

24. LUMBAR VERTEBRAE Support the abdomen One bone that results from the fusion of 3-5 vertebrae Attaches to pelvis SACRAL VERTEBRAE

25. COCCYGEAL VERTEBRAE Also called caudal or tail vertebrae Can be docked- spinal cord ends near the lumbosacral junction

26. AXIAL & APPENDICULAR SKELETON AXIAL SKELETON: SKULL, HYOID BONE,VERTEBRAL COLUMN, RIBS, STERNUM APPENDICULAR SKELETON: BONES OF THE LIMBS

27. SCAPULA (shoulder blade) Large triangular bone on the side of the thorax HUMERUS (upper arm) ULNA and RADIUS (forearm) Ulna forms the elbow CARPUS (wrist) Numerous short/irregular bones arranged in 2 rows

28. METACARPALS (palm) Vary in number between species (Ex: dog – 5, horse – 3) Numbered from medial to lateral DIGITS (toes) Numbered from medial to lateral PHALANGES are located within the digits Usually 3 phalanges in one digit (P1, P2, P3)

29. PELVIS (hip) 3 pairs of bones that fuse to become one IIium – the largest bone Flares out to the side Ischium – strongest, most caudal Pubis – Most ventral FEMUR (thigh) Longest bone in the body Forms part of the STIFLE (knee)

30. PATELLA (kneecap) TIBIA (shin) AND FIBULA Tibia is larger than fibula, and bears more weight

31. TARSUS (ankle) Called HOCK in animals Composed of numerous irregularly shaped bones arranged in rows METATARSALS (foot) Very similar to metacarpals Vary in number between species Numbered medial to lateral DIGITS (toes) Same as forelimb

32. JOINTS-an articulation between bones and cartilage that is held in place by ligaments SYNARTHROSES (Fibrous joints) no movement Ex: Skull AMPHIARTHROSES (Cartilaginous joints) slight movement Ex: Pelvis at pubic symphysis, vertebral column DIARTHROSES (Synovial joints) freely movable Most numerous in the body Ex: Hip joint, shoulder joint