Skeletal

Function Provide support for body tissues Protects organs Movement Production of blood cells(red, white, and platelets)- in the red marrow of the humerus, femur, sternum, ribs, vertebrae, and pelvis Store minerals-Ca and P

Skeleton Made of CaCO3 206 bones Joints- where 2 bones meet to allow for movement Bones held together by ligament-tough piece of connective tissue. Cartilage- flexible bone- ears, nose Some joints have cartilage for smooth movement of the bones against each other Muscle held to bone by tendon Some joints like shoulder have a bursae –fluid filled sac to decrease friction.

4 kinds of movable joints Ball and socket- shoulder and hip Hinge- knee and elbow Pivot- arm can twist Saddle- wrist- bones slide across each other

Immovable joints- skull plates Slightly movable- joint between tibia and fibula of lower leg

2 different types of bone Compact- hard,outer surface called periosteum. Has blood vessels and nerve endings that travel through Haversian canals. Spongy- less dense.Found at the end of long bones and in the middle of short flat bones Osteoblasts- produce new bone cells. Marrow- red produces blood cells yellow- fat

Bone Formation and Growth Embryos begin with skeleton made of flexible cartilage. This is replaced by bone called ossification Bones grow in length and diameter as you age. During puberty- sex hormones produced increase osteoblast mitosis which leads to growth spurt.

Skeletal Disorders Arthritis- inflammation of the joints Osteoporosis- loss of Ca.