The Skeletal System Flashcards
Sharpeys fibers
Made up of collagen and anchors periosteum to underlying bone surface
Where is a marrow cavity located?
Within the diaphysis
What covers epiphyses
Hyaline cartilage/ articular cartilage
Compact bone
A hard dense outer region that allows the bone to resist a linear compression and twisting
Where is spongy bone located
Inside compact bone
What does spongy bone allow long bones and bone marrow to do?
Resist forces from many directions and provides a cavity for bone marrow
What is the endosteum?
A thin membrane covering inner surfaces of bone cells involved in the maintenance of bone homeostasis
Epiphyseal lines
Separate proximal and distal epiphyses from diaphysis
What bones do not have diaphysess, epiphysess, medullary cavities, epiphyseal lines, or epiphyseal plates?
Short, flat, irregular, and sesamoid bones
What are sinuses?
Air sac filled spaces in some flat and irregular bones of the skull which reduced bone weight
What fraction of blood supply does the long bone get from the periosteum?
1/3
Where does the remaining 2/3 of blood supply come from to get to the periosteum ?
Nutrient arteries
What is red bone marrow?
Loose connective tissue that supports islands of blood forming hematopoietic cells
As a person gets older the amount of red bone marrow they have…..
Decreases
Where is red bone marrow in adults only found?
Pelvis, proximal femur and humorous, vertebrae, ribs, sternum, clavicles, scapula, and some bones of the skull
Why do children need more red bone marrow?
To assist in growth and development
What is yellow bone marrow composed of?
Triglycerides, blood vessels, and adipocytes
What is inorganic matrix made up of in bone tissue?
Minerals that make up 65% of the bones total weight
What is organic matrix made up of?
Collagen fibers and usual ECM components
Makes up 35% of bones weight
Periosteum
A membrane composed of dense irregular collagenous tissue that is tick with blood vessels and surrounds the outer surface of long bones
What is an osteoblast?
In active bone cell found in the periosteum and endosteum
Bone building cells that perform deposition
What is bone deposition?
Osteoblast secrete organic matrix materials and assist in formation of inorganic matrix
What are osteocytes?
Mature bone cells that surround themselves with bone matrix in the Lacuna
What are osteoclasts responsible for?
Responsible for bone resorption
What is bone resorption?
The process where cells secrete hydrogen ions in enzymes that break down bone matrix
What are lamellae or concentric lamellae?
Rings made up of thin layers of bone
What is the central canal (haversian)?
And endosteum lined hole found in the center of each osteon where blood vessels and nerves reside to supply bone
What is a lucunae
A small cavity found between lamellae
What are trabeculae?
Struts or ribs of bone
When does bone formation occur?
Embryo and fetus
Infancy, childhood, adolescence
Bone remodeling/repair
What is fontaneis?
Soft sport on a babies head
What is bone remodeling?
Continuous replacement of old bone tissue formation and loss
What are the five factors affecting bone remodeling?
Minerals, vitamins, hormones, activity level, diet
What does vitamin A do?
Stimulates osteoblasts
What does vitamin C do
Help synthesize collagen
What does vitamin D do?
Calcium resorption
What do parathyroid hormones do?
Stimulate osteoblasts
What does calcitonin do?
Stimulate osteoclasts
Comminuted fracture?
Splinted or crushed bone
Greenstick fracture
Partial fracture
Impacted fracture
One end of a fractured bone is forcefully driven into the interior of the other
Spiral fracture
Bone twists in opposite directions
Simple fracture
Bone breaks totally without breaking skin
What is demineralization
Loss of calcium and minerals from ECM
What is brittleness?
Decreased rate of protein synthesis and production of collagen fibers
Paget’s disease
Abnormal bone remodeling process
Osteoporosis
Deterioration of cartilage and bone
Osteophytes (bone spurs)
Bony projections developing along edges of bone/Near joints
Hallux valgus (bunions)
Enlargement of bone and joint of base of big toe
Rickets
Softening/weakening of bones due to lack of vitamin D
Scurvy
Abnormalities in bone development, epiphyseal disease, lifting of periosteum because of lack of vitamin D
Scoliosis
Curvature of the spine from side to side
Lordosis
Curvature of the spine from front to back
Kyphosis
Curvature of upper spine outward
Where are flat bones located?
Ribs, pelvis, sternum
Where are irregular bones located
Vertebrae and certain skull bones
Where are sesamoid bones located?
Kneecap and within tendons
What are the six functions of the skeletal system?
Protection, mineral storage and acid-base homeostasis, blood cell formation, fat storage, movement, support
