2The Skeletal System Function: Provides shape and support Allows movementProtects tissues and organsStores certain mineralsProduces blood cells
3The Skeletal SystemBones- A solid network of living cells and protein fibers that are surrounded by deposits of calcium.Structures of a bone:Periosteum- The tough layer outer layer of the bone.Compact Bone- contains Haversian canals that contain blood vessels and nervesSpongy Bone- found in the ends of bones and produces RBC.Yellow bone Marrow- made of fat cells.Red Marrow- Produces RBC, WBC, and platelets.
4The Skeletal SystemCartilage- Strong, connective tissue that supports the body. Softer and more flexible than bone*There are approximately 206 bones in the human body.*
5The Skeletal SystemCartilage is gradually replaced by bone during a process called ossification.Osteoblasts secrete mineral deposits that replace cartilage in developing bones.Osteocytes help maintain the minerals in bone tissue and continue to strengthen the growing bone.
6The Skeletal SystemLigaments- Hold bone to bone. Example: Hold bones together in knee; ACL.Tendons- Hold muscle to the bones. Example: Achilles tendon attaches to the calf.
7The Skeletal System Joint- is any place where two bones come together. -Types of Joints:Movable- prevent movement in one or more directions. Examples: pivot joint (radius and ulna); ball and socket (arm into shoulder)Semi-movable- allow a little bit of restricted movement. Example: Vertebrae.Immovable- allow no movement at all. Example: Skull
8The Skeletal System Skeletal Disorders: Arthritis: Inflammation of jointsOsteoporosis: loss of calcium in bones leading to weakening of bones
932.3 The Integumentary System: Hair, Skin, and Nails Function:Communication of pain, pressure, temperatureProtection of body:Prevents dehydrationRegulates body temperatureBarrier for disease/infectionCovers and holds in organsRemoves waste productsBarrier for sun’s UV rays
10The Integumentary System Epidermis: Outermost layer-Two layers:-Inner layer: living cells-Outer layer: dead cells-Contains:-Keratin- waterproofing-Melanocytes- produces pigment
11The Integumentary System Dermis: middle layerContains:-Hair follicles/roots-Sweat glands-Sebaceous (oil) glands-Arrector pili muscle-Nerves-Blood Vessels
13The Integumentary System Hair- made of dead epidermal cells.Function: protect skin from UV rays (on head); provide insulation from cold; hairs in nose, ears, eyelashes prevent dirt and other particles from entering body.Nails- Sheets of keratinized cellsFunction: protects tips of fingers/toes