First half of chapter 7 Flashcards
Bones and their dynamics
Bones and teeth are the most durable remains of a once-living body .Living skeleton is made of dynamic tissues, full of cells, permeated with nerves and blood vessels. Continually remodels itself and interacts with other organ systems of the body. Osteology is the study of bone
Skeletal system
Skeletal system—composed of bones, cartilages, and ligaments
Cartilage
Cartilage—forerunner of most bones
Covers many joint surfaces of mature bone
Ligaments
Ligaments—hold bones together at joints
Tendons
Tendons—attach muscle to bone
Functions of the Skeleton
: Support and protection
Support—limb bones and vertebrae support body; jaw bones support teeth; some bones support viscera
Protection—of brain, spinal cord, heart, lungs, and more
Functions of the Skeleton:Movement and electrolyle balance.
Movement—limb movements, breathing, and other movements depend on bone
Electrolyte balance—calcium and phosphate levels
Functions of skeleton: Acid–base balance,Blood formation
Acid–base balance—buffers blood against large pH changes by altering phosphate and carbonate salt levels
Blood formation—red bone marrow is the chief producer of blood cells
Bones and Osseous Tissue:Bone (osseous tissue)
Bone (osseous tissue)—connective tissue with the matrix hardened by calcium phosphate and other minerals
Bones and Osseous Tissue:Mineralization or calcification
Mineralization or calcification—the hardening process of bone
Bones and Osseous Tissue:Individual bones (organs)
Individual bones (organs) consist of bone tissue, bone marrow, cartilage, adipose tissue, nervous tissue, and fibrous connective tissue
General Features of Bones: flat and long bones
Flat bones Thin, curved plates Protect soft organs Long bones Longer than wide Rigid levers acted upon by muscles; crucial for movement
General Features of Bones: short and irregular bones
Short bones
Approximately equal in length and width
Glide across one another in multiple directions
Irregular bones
Elaborate shapes that do not fit into other categories
General Features of Bones:Compact bone
Compact bone—dense outer shell of bone.
Skeleton three-fourths compact and one-fourth spongy bone by weight.
General Features of Bones:Spongy (cancellous) bone
Spongy (cancellous) bone—loosely organized bone tissue
Found in center of ends and center of shafts of long bones and in middle of nearly all others
Covered by more durable compact bone
Long bone features:
Diaphysis,Epiphyses and Medullary cavity (marrow cavity)
Diaphysis—shaft that provides leverage Medullary cavity (marrow cavity)—space in the diaphysis of a long bone that contains bone marrow Epiphyses—enlarged ends of a long bone Strengthen joint and anchor ligaments and tendons
Articular cartilage
Articular cartilage—layer of hyaline cartilage that covers joint surface; allows joint to move more freely
Nutrient foramina
Nutrient foramina—minute holes in bone surface that allows blood vessels to penetrate
Periosteum
Periosteum—external sheath covering most of bone
Outer fibrous layer of collagen
Outer fibrous layer of collagen
Some fibers continuous with tendons.Perforating fibers—penetrate into bone matrix
Inner osteogenic layer
Inner osteogenic layer of bone-forming cells
Important to bone growth and healing of fractures
Endosteum
Endosteum—thin layer of reticular connective tissue lining marrow cavity
Has cells that dissolve osseous tissue and others that deposit it
Epiphyseal plate (growth plate)—
Epiphyseal plate (growth plate)—area of hyaline cartilage that separates epiphyses and diaphyses of children’s bones
Enables growth in length
Epiphyseal line—in adults, a bony scar that marks where growth plate used to be.
Flat bone
Flat bone Sandwich-like construction Two layers of compact bone enclosing a middle layer of spongy bone Both surfaces covered with periosteum Diploe—spongy middle layer Absorbs shock Marrow spaces lined with endosteum
