SKELETAL SYSTEM SKELETAL SYSTEM DEFINITIONS

January 17, 2018 Off By admin
Term Definition
TENDONS connects bone to muscle
LIGAMENTS connects bone to bone
OSTEOBLASTS creates new bone cells
OSTEOCLASTS breaks down bone cells
OSTEOCYTES bone cells
CALCIUM PHOSPHATE a mineral found in bone
CALCIUM CARBONATE a mineral found in bone
COLLAGEN helps form matrix in which minerals are deposited
COMPACT BONE forms outer shell of all bone
SPONGY BONE found at the end of long bones and the middle of flat bones
HARVERSIAN SYSTEMS in compact bone, bone cells that are arranged in concentric circles
HARVERSIAN CANALS in compact bone, rings that surround a branching system of canals containing nerves and blood vessels
LACUNA in compact bone, osteocytes are surrounded by small space. contains tissue fluid
LAMELLAE in compact bone, osteocytes secrete a hard calcified matrix which fills the spaces
CANALICULI narrow canals pass through the layers of matrix allowing tissue fluid to pass between cells providing osteocytes with nutrients and oxygen. in compact bone
TRABECULAE mesh work of thin plates in the spongy bone
EXAMPLES OF LONG BONE humerus, radius, ulna, femur, tibia, fibula
RED BONE MARROW makes new blood cells, red blood, white blood cells and platelets.
YELLOW BONE MARROW made up of fat cells and make some types of white blood cells
OSSIFICATION the process of laying down new bone material
DIAPHYSIS long hollow shaft of long bones
EPIPHYSES two rounded heads head at each end of long bones
ARTICULAR CARTILAGE slippery cartilage that covers the heads of long bones, which are spongy bone.
PERIOSTEUM tough sheath of connective tissue that covers bone
MEDULLARY CAVITY contains marrow
ENDOSTEUM connective tissue membrane
ENDOCHONDRAL OSSIFICATION skeleton of developing embryo is formed of cartilage
ENDOCHONDRAL OSSIFICATION STAGE 1 a model of the bone is first laid down in cartilage
ENDOCHONDRAL OSSIFICATION STAGE 2 the cartilage is invaded by osteoblasts which replace the cartilage with bone
ENDOCHONDRAL OSSIFICATION STAGE 3 proceeds until the cartilage is replaced by bone except for two strips of cartilage, mataphysis or (epiphyseal plates). A layer of cartilage covers the headsof the bone where they form a joint
ENDOCHONDRAL OSSIFICATION STAGE 4 bone in the centre of the shaft breaks down (osteoclasts) and is replaced by fatty marrow
METAPHYSIS (EPHIPHYSEAL PLATES) strips of cartilage
INTRAMEMBRANOUS OSSIFICATION cells cluster together to form a centre of ossification and differentiate into osteoblasts
ENDOCHONDRAL GROWTH growth of the bone in length
APPOSITIONAL GROWTH growth of the bone in width
REQUIREMENTS FOR BONE GROWTH calcium, magnesium, phosphorus, vitamin D, vitamin C, oestrogen
HORMONE AND CALCIFICATION hormone produced by the thyroid gland in response to high calcium levels
HORMONE AND DECALCIFICATION parathyroid hormone produced by glands in response to low blood calcium levels