Skeletal System 1
Skeletal system Skeletal system includes: bones of the skeleton, cartilage and ligaments Functions: Support (structural support of whole body) Storage of minerals (calcium) Storage of lipids (yellow marrow) Blood cell production (red marrow) Bone houses stem cells that produce RBCs, WBCs & platelets Protection Movement (bones and skeletal muscles provide movement) Bones act as levers that move when attached muscles contract 2
Axial Skeleton Lies in the midline of the body Bones of the axial skeleton: Skull Hyoid bone The vertebral column The thoracic cage Middle ear bones 3
Vertebral Column (Spine) Supports rib cage Serves as a point of attachment for the pelvic girdle Protects the spinal cord Cervical vertebrae 7 bones of the neck Thoracic vertebrae 12 bones of the torso Lumbar vertebrae 5 bones of the lower back Sacrum bone inferior to the lumbar vertebrae articulates with hip bones Coccyx 4
Abnormalities Lordosis exaggerated lumbar curvature Kyphosis increased roundness of the thoracic curvature Scoliosis abnormal lateral curvature that occurs most often in the thoracic region 5
Joints (Articulations) Three types of joints: Fibrous Cartilaginous Synovial Fibrous joints fibrous connective tissue joins bone to bone typically immovable examples: sutures of cranium tooth in socket 6
Joints (Articulations) Cartilaginous joints bones are joined by fibrocartilage or hyaline cartilage typically slightly movable examples between adjacent bodies of vertebral bodies pubic symphysis of the pelvis between ribs and sternum 7
Joints (Articulations) Synovial joints bones do not touch each other bones are separated by a joint cavity typically freely movable but have to be stabilized via ligaments, muscles, etc. examples: 8
Properties of Synovial Joints synovial membrane lines joint cavity produces synovial fluid (lubricant) ligaments (bone to bone connection) - support, strengthen joints sprain - ligaments with torn collagen fibers tendons (bone to muscle connection) - help support joint bursae - pockets of synovial fluid in CT (lined by synovial membrane) cushion areas where tendons or ligaments rub; shock absorbers 9
Movements Permitted By Synovial Joints 10
Joint Damage and Repair Cartilage and bone deteriorate with age cartilage can undergo calcification interferes with diffusion of nutrients/wastes through cartilage Joints can also become damaged by overuse or chronic inflammation Arthritis joint inflammation and destruction Osteoarthritis deterioration of the articular cartilage Rheumatoid arthritis synovial membrane inflamed & grows thicker autoimmune cause (immune system mistakenly attacks synovial membrane) 11
MUSCLES 12
Smooth Muscle location: walls of hollow organs & blood vessels regulation of contraction: involuntary rhythmic contraction: yes, in digestive system muscles, in uterus during childbirth 13
Cardiac Muscle location: heart regulation of contraction: involuntary, has its own pacemaker, but nervous and endocrine system also influence heart rate rhythmic contraction: yes intercalated discs - permit contractions to spread quickly throughout the heart (gap junctions) 14
Skeletal Muscle location: attached to bones, skin regulation of contraction: voluntary, but some skeletal muscles also controlled unconsciously rhythmic contraction: no fascia connective tissue that separates muscles from each other and the skin 15
Anatomy of Skeletal Muscle Organization of Connective Tissues 1) Epimysium epi = on surrounds entire muscle dense layer of collagen fibers separates muscles from surrounding tissues/organs fibers continue as strong, fibrous tendon (attached muscle to bone) 16
Anatomy of Skeletal Muscle Organization of Connective Tissues 2) Perimysium peri = around divides skeletal muscle into compartments (fascicles) fascicles = bundles of muscle fibers/cells) 17
Anatomy of Skeletal Muscle Organization of Connective Tissues 3) Endomysium endo = inside surrounds individual skeletal muscle cells (muscle fibers) loosely connects adjacent muscle fibers 18
Term Break Down Myasthenia Gravis Levoscoliosis Polymyositis Spondylolisthesis Rhabdomyosarcoma Icteric Osteoarthritis Hemiparesis Hemarthrosis Encephalitis Osteoporosis Pruritic Gangrenous Necrotic Oligodendroglioma Ecchymosis Cephalgia Hematoma Torticollis Polymyalgia