Skeletal System Health Science 1

Bone Formation Osteocyte: mature bone cell Osteoblast- bone cells that deposit new bone…. Osteoclast- Cell that absorbs bone Ossification- mineral matter starts to replace previously formed cartilage, creating bone Fontanel- baby’s soft spot

Types of Bone Long bone- bone of arms and legs Flat bones- bones of skull and ribs Irregular bones- spinal column Short bones- wrist

Structures of Long Bones Diaphysis- shaft Epiphysis- ends Medullary canal- center of the diaphysis Endosteum- lining of the marrow canal that keeps the cavity intact Periosteum- outside covering of the bone Articular cartilage- smooth, white tissue that covers the ends of bones where they form joints

Axial Skeleton Contains the skull, spinal column, ribs, sternum, hyoid Axial Skeleton is BLUE

Skull Bones Frontal bone Occipital bone 2 Parietal bone 2 Temporal bone Nasal bone Mastoid process Styloid process Vomer Zygomatic arch Mandible Maxilla Hyoid bone External Auditory Meatus

Skull bones

Spinal Bones Vertebral structure Cervical vertebrae-7 Body, foramen, spiny process Cervical vertebrae-7 Thoracic vertebra-12 Lumbar vertebrae-5 Sacrum-1 Coccyx-1

Ribs and Sternum Sternum divided into 3 parts – bottom tip is XIPHOID PROCESS  12 pairs of ribs 7 true ribs: connect to sternum 3 false ribs: connect to cartilage of 7th 2 floating

Hyoid bone Not attached to any other bones Supports tongue weight

Appendicular Skeleton Contains upper extremities, shoulder girdles, arms, wrists, and hands, lower extremities, hip girdle legs, ankles, and feet Appendicular Skelton is beige

Shoulder Girdle and Arm clavicle – collar bone scapula – shoulder blade humerus – upper arm radius and ulna – lower arm (radius thumb side) carpals – wrist bones – held together by ligaments metalcarpals – hand bones phalanges – fingers

Pelvic Girdle and Legs pelvis – 3 bones (ilium, ischium, and pubis) femur – upper leg, longest and strongest bone in body tibia and fibula – lower leg patella – kneecap tarsal bones – ankle calcaneus – heel bone metatarsals – foot bones Phalanges-toes

Joints Ball and socket One bone has a ball at one end The other has a concave socket Allows for the greatest range of motion Ex: shoulder

Joints Hinge joint Move in one direction or plane ex: knee

Joints Pivot joints Bones that rotate across each other Ex: shake head no

Joints Gliding joints– flat surfaces glide across each other Ex: Vertebrae of spine

Joints point of contact between two bones Bursa: sac that contains synovial fluid to prevent friction at a joint Synovial fluid: the lubricating substance between two bones Arthroscopy: examination into a joint using a fiber optic lens

http://www.youtube.com/watch?v=abgJD054sds http://www.youtube.com/watch?v=Jpvuqj5nv6U http://www.youtube.com/watch?v=JUDaGQ_oosc