BONES 2 JOINTS 3 MUSCLES 1 206 BONES

BONES 2. JOINTS 3. MUSCLES 1.

� 206 BONES make up the human skeleton � Femur 60 cm – Ossicles (size of a pea) - HEAD - LONG legs, arms - TRUNK - SHORT wrists, heels - LIMBS - FLAT skull, ribs - IRREGULAR backbone � A bone is a hard solid organ that forms part of the skeleton � Diaphysis: thin part � Epiphyses: rounded extremities � Bone marrow: soft, fatty substance and blood vessels (inside Diaphysis)

� FUNCTIONS 1 – SUPPORT bones form a rigid structure that makes up the framework of our body. This holds our posture when standing, sitting, or crouching. Acts as an anchor for soft organs (muscles, heart, lung) 2 – PROTECTION bones protect our internal organs (lungs, heart and skull) 3 – MOVEMENT bones act as levers during muscle movement, allowing us to move around or to raise one part of our body. Structure is rigid and flexible 4 – STORAGE internal cavities of bones store fat, while bony tissues store minerals (calcium, phosphorus). They allow for exchange to supply our bodies when needed 5 – PRODUCTION OF BLOOD CELLS bone marrow of certain bones produce red, white blood cells and platelets

� THE JUNCTION BETWEEN TWO OR MORE BONES � JOINT CAPSULE: - Synovial fluid (lubricates entire joint capsule) - Cartilage (whitish, elastic smooth tissue to minimize bone wear and tear when rubbing) - Ligament (fibrous bands of tissue attaching bones) � MOBILITY: - Fixed (skull – connected) - Semi-movable (spinal cord, ribs – provide protection but flexible for movement) - Freely-movable (elbow, hip – provides a wide variety of movement)

� MECHANICS OF JOINTS 1 – EXTENSION / FLEXION * increases OR decreases the angle between bones 2 – ABDUCTION / ADDUCTION * increases OR decreases the distance between a limb and the body 3 – ROTATION * a movement around an axis

� MUSCLES ARE THE FIBRES FOUND ON BONES AND VARIOUS ORGANS THAT HAVE THE ABILITY TO CONTRACT CAUSING OUR BODIES OR OUR INTERNAL ORGANS TO MOVE FUNCTION DESCRIPTION MOVEMENT Make the mobility of our body’s limbs possible. Voluntary/involuntary. Contraction followed by release. POSTURE MAINTENANCE Core muscles. Stabilizing muscles. These muscles work continuously to maintain posture and form. JOINT STABILIZATION Movements support and stabilizes joints. Without these muscles, some joints would not remain in place HEAT RELEASE 75% of contracted muscle energy is transformed into heat. Lost energy (sweat) helps maintain body temperature

� SKELETAL MUSCLES - Voluntary muscles - Attached to bones (tendon) Rapid reaction (short time – contraction) Tire easily (low endurance) - � SMOOTH - Involuntary muscles Walls of certain internal organs Weaker (more endurance) � CARDIAC - MUSCLES Muscles that make up the heart Involuntary, great endurance (like smooth muscles) Structure, strength (like skeletal muscles)