Anatomy Lab #2 – Axial Skeleton Name ___________________

Book Reference: Chapters 5 & 6

Goals for this lab:

1. Identification of basic bone structure
2. Identification of axial bones
3. Identification of axial bone landmarks

Part I: Basic Bone Anatomy

1. Define diaphysis. Shaft of the bone

2. Define epiphyses. Extremities of the bone

3. Define metaphyses. Region where the diaphysis & the epiphyses meet

4. What is the epiphyseal plate. Layer of hyaline cartilage that allow the bone to grow lengthwise

5. Define articular cartilage. Cartilage that covers the epiphyses; reduces friction at the joint

6. Define periosteum. What are the 2 layers of the periosteum. Connective tissue covering the diaphysis; fibrous outer layer & osteogenic inner layer

7. Define medullary cavity. Space within the diaphysis containing fatty yellow marrow

8. Define endosteum. Membrane which lines the medullary cavity

9. What is hydroxyapatite (tricalcium phosphate)? What is calcium carbonate? Are they both part of the matrix? Both are mineral salts that makes up the bone; Yes

10. Name the 4 types of bone cells & list their function or characteristics. Osteoprogenitor cells - develop into osteoblasts, mitotically active; osteoblasts - secrete collagen, no mitotic ability; osteocytes - mature bone cells, maintain daily metabolic activity; osteoclasts - modified monocytes that breakdown & reabsorb bone

11. What is an osteon? Basic structural unit of bone = Haversian system

12. Define lamellae. Concentric rings of hard, calcified matrix

13. Define lacunae. Spaces that contain osteocytes

14. Define canaliculi. Canals connecting lacunae with each other & the central canals; conduit system for nutrient & waste transport

15. What is the function of Volkmann’s canals. Canals connecting the vessels of the periosteum with the Haverian canals & the medullary cavity

16. Does spongy bone contain osteons? Haversian canals? NO; NO

17. What is the difference between intramembranous & endochondral ossification? Intramembranous ossification is the formation of bone directly on or within fibrous CT; Endochondral ossification is the formation of bone from a cartilage model

18. Name the 4 zones of the epiphyseal plate. Resting, Proliferating, Hypertrophic, Calcified

Part II: Bone markings

19. What is a fissure? Narrow, cleft-like opening between adjacent parts of bones through which blood vessels or nerves pass

20. What is a fossa? A depression in or on a bone

21. What is a condyle? Large, rounded protuberance at the end of a bone; forms a joint

22. What is a facet? Smooth, flat surface; forms a joint

Part III: Axial Skeleton

23. Name the bones of the cranium? Frontal, Parietal (2), Temporal (2), Occipital, Sphenoid, Ethmoid

24. Name the bones of the face? Nasal (2), Maxillas (2), Zygomatic (2), Mandible, Lacrimal (2), Palatine (2), Inferior nasal conchae (2), Vomer

25. What is the significance of the zygomatic processes of the temporal bones? Possesses mandibular fossa & articular tubercle which articulates with the condylar process of the mandible to form the temporomandibular joint

26. What is the significance of the mastoid processes of the temporal bones? Attachment point for neck muscles

27. What is the significance of the foramen magnum of the occipital bone? Allows the spinal cord & blood vessels to pass into & out of the brain

28. What is the significance of the occipital condyles of the occipital bone? They articulate with the atlas

29. What is the significance of the sella turcica of the sphenoid bone? Cradles the pituitary gland

30. What is the significance of the cribiform plate of the ethmoid bone? Contains olfactory foramina which allow the olfactory nerves to enter the brain from the nasal cavity

31. What is the significance of the crista galli of the ethmoid bone? Attachment points for the brain membranes (meninges)

32. What are alveolar processes? Where do you find them?