Skeletal System Chapter 15 Lessons 1 and 2 The Skeletal System

PURPOSE OF BONES Serve as a place for muscles to attach. Serve as protection for internal organs. Principle storage for essential minerals that promote strong bones. Center for production of red and white blood cells.

SKELETAL DIAGRAM

NUMBER OF BONES ADULT SKELETAL SYSTEM BABY SKELETAL SYSTEM 206 BONES IN ADULTHOOD AFTER OSSICFICATION (FUSION OF BONES) 350 BONES AT BIRTH MANY OF THESE BONES WILL GO THROUGH OSSIFICATION

STRUCTURE AXIAL SKELETON: includes the 80 bones of the skull, spine, ribs, and sternum or breastbone, Protects spinal cord…vertebrae. Protects heart and lungs…rib cage.

AXIAL SKELETON BREAKDOWN Skull = 8cranium, 3 in the inner ear, and the hyoid (a single bone in the neck, the only bone that does not attach to another bone). Vertebral Column = 26 individual bones Thorax (chest cavity) = the sternum and 12 pairs of ribs First 7 pair are true ribs – attach directly to sternum Next 3 pair are false ribs – attach indirectly to sternum Last 2 pair are floating ribs – do not attach to sternum

STRUCTURE APPENDICULAR SKELETON: includes the 126 bones of the shoulders, arms, hands, hips, legs, and feet. Main purpose is movement.

TYPES OF BONES… LONG – greater length that width and slightly curved for strength. Curved to absorb stress of body weight. Femur Arms and Legs Ends form joints and connect to other bones.

SHORT… nearly equal in length and width. Wrists, ankles, hands, feet. 50% are found in the hands and feet.

FLAT…offer protection for internal organs and provide attachment for muscles. Ribs, skull bones. Protect vital organs such as the Brain.

IRREGULAR… unusual shapes that do not fit in other types. Vertebrae. Bones that don’t have a specific shape.

CARTILAGE Strong, flexible, connective tissue. Line the surfaces of joints to allow smooth movement. Cushion adjoining vertebrae. Support nose and ears. OSSIFICATION: the process by which bone is formed, renewed, and repaired.

CARTILAGE

Ligaments Tough bands of fibrous, slightly elastic tissue that bind the bond ends at the joint. Prevent excessive movement at the joint. TENDONS: Fibrous cords that join muscle to bone or to other muscles.

JOINTS The point at which two bones meet. PIVOT JOINT: a bony projection allows rotation. Joint between head and neck that allows head to rotate.

JOINTS The point at which two bones meet. BALL-AND-SOCKET-JOINT: allows the widest range of movement. Shoulder and Hip Joints

GLIDING JOINT Allow bones to slide over one another. Wrist Ankle

HINGE JOINT Allow a joint to bend and straighten Fingers, knee and elbow.

CARE AND PROBLEMS OF THE SKELETAL SYSTEM CHAPTER 15 LESSON 2 CARE AND PROBLEMS OF THE SKELETAL SYSTEM

CARE of the SKELETAL SYSTEM Good nutrition/CALCIUM Exercise (Bone Mass) Safety

FRACTURES Fractures can be detected by Doctors through the use of X-Ray A FRACTURE IS ANY TYPE OF BREAK IN A BONE….

TYPES OF FRACTURES COMPOUND – fracture in which the broken end of the bone protrudes through the skin. SIMPLE – fracture n which the bone does not protrude through the skin. HAIRLINE-the fracture is incomplete and the two parts of the bone do not separate. TRANSVERSE – the fracture is completely across the bone. COMMINUTED – the bone shatters into more than two pieces.

INJURIES TO THE JOINTS DISLOCATION – ligaments that attach the bone at the joint are torn as the bone slips out of place. TORN CARTILAGE – cartilage tears as the result of a hard blow or twisting of a joint. BURSITIS – inflammation of the bursa sac, which is a fluid filled sac that helps to provide smooth movement inside a joint. BUNION – swelling of the bursa in the joint of the big toe. ARTHRITIS – the inflammation of a joint, usually caused by wear and tear on the joints.