Journal #5: How many bones are in the human body? Do you think there are more in your axial or appendicular skeleton? Fun Fact: The only bone in the human body not connected to another is the hyoid, a V-shaped bone located at the base of the tongue. Objective: –Describe the function of the skeletal system –Classify bones according to their shapes and markings –Compare the structure and function of compact and spongy bone

Part I: Gross Anatomy and Histology pgs Ch. 6 Osseous Tissue & Bone Structure

Function of the Skeletal System Support: Framework for the attachment of tissues and organs Storage of Minerals & Lipids: Calcium and Lipids in Marrow Blood Cell Production: Red marrow produces both red and white blood cells Protection: Surrounds delicate organs Leverage: range of motion

Gross Anatomy Types of Bones (206 bones total) –Long: long and slender; arm, legs, fingers, toes –Flat: thin and parallel; sternum, ribs, scapula, top of skull –Sutural: flat and irregularly shaped puzzle pieces of the skull –Irregular: complex shapes; vertebrae –Short: small & boxy; wrists & ankles –Sesamoid: small, flat, shapes like a seed; patella

Bone Markings Surface features which help to describe a bone –Elevations & projections: process or ramus –Processes formed where tendons or ligaments attach: trochanter, tuberosity, tubercle, crest, line, spine –Processes formed for articulation with adjacent bones: head, neck, condyle, trochlea, facet –Depressions: fossa or sulcus –Openings: foramen, canal, fissure, sinus or antrum

Bone Structure Long bones –Diaphysis: long tubular shaft (compact bone with a marrow cavity in the center) –Epiphysis: expanded area at end (mainly spongy bone with a thin cortex of compact bone) –Metaphysis: area between epi and dia Flat bones –Cortex of compact bone with Diploe of spongy bone in the center

Journal #8: Is it a projection, depression, or opening? See page 182 Tuberosity Fissure Sulcus Sinus Process Objective: –Describe the function of the skeletal system –Classify bones according to their shapes and markings –Compare the structure and function of compact and spongy bone *B1 computer lab tomorrow!!!

Structure of a Long Bone

Use the Femur Bone to label the following: pg. 182 Trochanter: large rough projection where tendons or ligaments attach Head: Expanded articular end of an epiphysis (separated from the shaft by a neck) Neck: Narrow connection between epiphysis and diaphysis Tubercle: small rounded projection when tendons or ligaments attach Facet: A small flat articular surface Condyle: smooth rounded articular process (bump) Epiphysis/ Diaphysis/ Metaphysis

On Humerus Label: Tubercle Head Sulcus Neck Tuberosity Fossa Trochlea Condyle & Epiphysis, Diaphysis, Metaphysis

Bone Histology (Tissues) (bone notes part 2) Supporting connective tissue Matrix made of calcium salt deposits with collagen fibers Cells: –Osteocytes: mature bone cells that maintain the bone matrix and repair damaged bone –Osteoblasts: immature bone cells that secrete matrix components –Osteoprogenitor cells: stem cells which produce osteoblasts –Osteoclasts: cells that remove and recycle bone in a process called osteolysis

Structure of Compact Bone Each unit is an osteon (Haversion System) –Osteocytes arranged in concentric layers around a central canal (Haversion Canal) Each canal contains one or more blood vessels Run parallel to surface of bone Perforating canals run perpendicular –Concentric lamella add strength and resiliency –Interstitial lamellae between osteons with space between called canaliculi –Cirumferential lamellae found at outer and inner surface of bone (covered by either periosteum or endosteum)

Structure of Spongy Bone Not arranged in osteons Matrix forms branching trabeculae No capillaries or venules; diffusion through canaliculi Located where bone is not heavily stressed (reduces the weight of the skeleton) Protects marrow (red- blood cell formation, yellow adipose storage)

Periosteum & Endosteum Periosteum –Isolates bone from surrounding tissue –Circulation & nerve supply –Bone growth & repair –Collagen fibers are continuous with joint capsules & attached tendons and ligaments Endosteum –Lines the marrow cavity –Layer of osteoprogenitor cells –Growth, repair, remodeling

Journal #9: Read Clinical Note “Abnormal Bone Growth & Development on pg. 196 Which gland irregularity causes a type of dwarfism? Is acromegaly a result of cartilage or bone growth post puberty? What is a characteristic of Marfan’s Syndrome? Objective: –Describe the remodeling and homeostatic mechanisms of the skeletal system –Discuss the effects of nutrition, hormones, exercise, and aging on bone development. –Describe how fractures heal.

Journal #5: Read “Types of Fractures” on pg Which type of fracture is usually the simplest to treat? Who is most likely to have a greenstick fracture? Why? When is a Colles’ fracture likely to occur? Objective 4: –Discuss how bone grows, heals, and remodels itself. –Know the conditions that affect bone growth.