Chapter 6 Bones and Skeletal Tissues Flashcards
Which type of cartilage is most plentiful in the adult body
What two body structures contain flexible elastic cartilage?
The epiglottis and external ear cartridges
Cartilage grows by interstitial growth. What does this mean?
it is from within
What are the components of the axial Skeleton?
Skull, Thoracic, and Vertebral
What bone class do the ribs and skull bones fall into?
What are the 7 functions of bones?
Support, Protect, Movement, Mineral& growth factor storage, blood cell formation, fat storage, hormone production
What is the functional relationship between skeletal muscles and bones?
Skeletal muscles use bones as levers to cause movement of the body and its parts.
What two types of substances are stored in the bone matrix?
Stores mineral and growth factors
Describe two functions of a bone marrow cavities.
Serve as sites for blood cell formation and fat storage
What are the 3 levels of bone structure?
Gross, Microscopic, and chemical
What is the functional importance of bone markings?
Serve as sites of muscle, ligament, and tendon attachment, as joint surfaces, or as conduits for blood vessels and nerves.
What are the five type of bone cells?
Osteogenic, Osteoblast, Osteocytes, Bone lining cells, osteoclasts
The structural unit of compact bone, consists of a central canal surrounded by concentric lamellae of bone matrix.
What is The Osteon?
The spidery _____ are mature bone cells that occupy spaces (lacunae) that conform to their shape. They monitor and maintain the bone matrix.
What is the Osteocytes?
Slender trabeculae containing irregular lamellae, which enclose red marrow-filled cavites
What is Spongy bone?
Include bone cells, The extra cellular matrix includes osteoid, That are secreted by osteoblast and give the bone strength
What is Organic components?
Hydroxyapatites make bone hard
What is Inorganic components?
Are crest tubercles and spines.
-Bony projections or depressions?
How does the structure of compact bone differ from that of spongy bone when viewed with the naked eye?
Compact bone looks solid and homogenous. Spongy bone has an open network of bone spicules.
Delicate connective tissue membrane, covers internal bone surfaces, covers trabeculae of spongy bone and lines canals that pass through compact bone
What is Endosteum?
Which bone-- organic or inorganic-- makes it hard?
what is Inorganic?
(the bone salts)
Which cell has a ruffled border and acts to break down bone matrix?
What is the Osteoclast?
The process of bone formation..
What is Ossifaction?
The Bone develops by replacing hyaline cartlidge. The resulting bone is called a cartlidge..
What is Endochondral Ossification?
A bone develops from a fiborus membrane. The bone is called membrane bone
What is Intramembranous?
What are the steps taken in the process of ossifcation to begin..
1) A bone collar forms around diaphysis of the hyaline cartlidge model. 2) Cartlidge in the center of the diaphysis calcifies and the develops cavities 3) The periosteal bud invades the internal cavities and spongy bone forms. 4) The diaphysis elongates and a medullary cavity forms. Secondary ossification centers appear in the epiphyses. 5) The epiphyses ossify. When completed, hyaline cartlidge remians only in the epiphyseal plates and the articular cartlidges.
Essentially all bones below the base of the skull except for the clavicle are formed by the..
What is Endochondral Ossifcation?
Forms the cranial bones of the skull. (frontal, parietal, occipital, and temporal bones) and the clavicles,,
What is Intramembranous Ossification?
Intramembranous Ossification involves four major steps. What are they?
1) Ossifaction centers appear in the fibrous connective tissue memebrane. 2) Osteoid is secreted within the fibrous membrane and calcifies. 3) Woven bone and periosteum form. 4) Lamellar bone replaces woven bone, just deep to the periosteum. Red marrow appears.
Long bones increase in length by _______ growth of the epiphyseal plate cartilage and its replacement by bone.
What is Interstitial growth?
Increases bone diameter/ thickness
What is Appositional growth?
Bones don't begin with bone tissue. What do they begin with?
at the fibrous membrane or hyaline cartilage
When describing endochondral ossification, some say "bone chases cartilage." What does this mean?
Cartilage grows, then brakes down and is replaced by bone.
Where is the primary ossification center located in a long bone?
The center of the shaft
Where is the the secondary ossification center located?
In the epiphyses. (bones ends)
As a long bone grows in length, what is happening in the hypertrophic zone of the epiphyseal plate?
The chondrocytes are enlarging and their lacunae are breaking down and leaving holes in the cartilage matrix
The single most important stimulus of epiphyseal plate activity is...
Modulates the activity growth hormone, ensuring that the skeleton has proper proportions as it grows..
What is Thyroid hormones?
Bone deposit and bone resorption occur at the surfaces of both the periosteum and the endosteum. Together, the two processes constitute….
What is bone remodeling
What coordinates bone remodeling?
"Packets" of adjacent osteblast and osteoclasts called remodeling units.
What are the fracture classifications?
position of bone ends after fracture, completeness of the break, Whether the bone ends penetrate the skin.
What are the four major stages in repair for a simple fracture?
1) Hematoma Forms(a mass of clotted blood, forms at the fracture site) 2) Fibrocartilaginous forms (splints the broken bone) 3) Bony callus forms ( New bone trabeculae appear in the fibrocartilaginous callus and gradually convert to bony callus of spongy bone) 4)Bone remodeling occurs ( begins during bony callus,bony callus is remodeled. Comapct bone is laid down to reconstruct the shaft walls)
If osteoclasts(bone destroying cells) in a long bone are more active then osteoblasts,(bone forming cells) how will bone mass change?
Bone mass will decrease
Bone ends are exposed to the external enviorment
What is an open fracture?
Bone ends do not penetrate the external boundry
What is a closed fracture?
Increases bone mass, as during childhood or when exceptional stress is placed on the bones..
What is bone growth?
Follows bone growth to maintain the proper proportions of the bone considering stresses placed upon it..
What is bone remodeling
Looks solid and homogenous
What is compact bone
Has an open network of bone spicules
what is spongy bone?
Forms the long axis of the bone, is made out of a thick collar of comapct bone that surrounds medullary cavity.
What is Diaphysis?
Are the bone ends, are broader than diaphysis
What is Epiphyses?
Are active stem cells found in the membranous periosteum and endosteum
What is Osteogenic Cell?
Matrix- synthesizing cell responsible for bone growth
What is osteoblast?
Mature bone cell that monitors and maintains the mineralized bone matrix
What is osteocytes?