Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
85 Cards in this Set
- Front
- Back
What is osteology? |
the study of bones |
|
What are the 5 functions of the skeletal system? |
support protection body movement mineral storage hemopoesis |
|
How does the skeletal system offer support? |
it is the framework of the body muscles can attach to frame |
|
How does the skeletal system help bodily movement? |
the bones act like levers that muscles pull |
|
What percent of calcium is stored in bones? |
95% |
|
what percent of phosphorus is stored in the bones? |
90% |
|
Why does the body need phosphorus? |
plasma membrane repair ATP |
|
Why does the body need calcium? |
muscle contraction blood clotting nerve impulses |
|
What is hemopoesis? |
production of blood cells |
|
Where does hemopoesis occur? |
in the red bone marrow |
|
Is red bone marrow spongy or compact? |
spongy |
|
Where is red bone marrow located in adults? |
axial skeleton (flat bones of skull, sternum, ribs, vertebrae, hip bones) proximal epiphyses of humerus and femrur |
|
What are the 4 bone shapes? |
Long Short Flat Irregular |
|
What is a long bone? |
bones that are longer than they are wide cylindrical bone shaft |
|
What are short bones? |
approximately as long as they are wide |
|
What are flat bones? |
relatively thin broad surface for muscle attachment thin layer of spongy bone in between compact bone |
|
What are irregular bones? |
have irregular and varied shapes |
|
What is a diaphysis?
|
cylindrical shaft of a bone |
|
what is the medullary cavity? |
the hollow inside of a diaphysis |
|
What lines the medullary cavity? |
endosteum |
|
What is endosteum? |
dense irregular connective tissue |
|
In adults, what does the medullary cavity contain? |
yellow bone marrow |
|
What is the epiphysis of a bone? |
the end of the bone |
|
what is the proximal epiphysis? |
the epiphysis closer to the attachment point of the trunk |
|
what is the distal epiphysis? |
the epipysis farther away from the attachment point of the trunk |
|
What is articular cartilage? |
hyaline cartilage on the epipyses |
|
what is the function of articular cartilage? |
reduces friction helps connecting bones move more easily |
|
What is the epiphyseal plate? |
hyaline cartilage plate between diaphysis and epipysis |
|
Is the epiphyseal plate in growing or mature bone? |
growing |
|
What does the epiphyseal plate become in mature bone? |
epiphyseal line |
|
what is periosteum? |
dense irregular tissue that covers outside of bone |
|
What surface is periosteum not found on bones? |
not found on articular surfaces of bone |
|
What are perforating fibers? |
protein fibers that anchor periosteum to bone |
|
is the periosteum vascular or avascular? |
vascular |
|
What is the function of the periosteum? |
bone width growth |
|
What are the 3 different types of bone cells? |
osteoblasts osteocytes osteoclasts |
|
What is an osteoblast? |
immature bone cells that create bone |
|
What are osteocytes? |
mature bone cells that maintain bone matrix |
|
What are osteoclasts formed from? |
fused red bone marrow cells |
|
What is the function of osteoclasts? |
they breakdown and resorb bone |
|
Is an osteon part of spongy or compact bone? |
Compact |
|
What are osteons? |
cylindrical structures that run parallel to length of diaphysis |
|
What 5 parts make up Osteons? |
central canal concentric lamellae osteocytes lacunae canaliculi |
|
What is the central canal in osteons? |
opening that contains blood vessels and nerves |
|
Does the central canal run parallel, perpendicular, or oblique to the diaphysis? |
parallel |
|
How many central canals are in one osteon? |
one |
|
What are the concentric lamellae? |
concentric rings of bone matrix |
|
What is the lacunae? |
the space where the osteocyte resides |
|
what are the canaliculi? |
Tiny channels that radiate from lacunae |
|
What is the function of the cancaliculi? |
provide for exchange of nutrients/ wastes between central canal and osteocytes |
|
What is the perforating canal? |
canal that runs perpendicular to the central canals connect multiple central canals |
|
what is the interstitial lamellae |
incomplete remnants of osteons |
|
do interstitial lamellae have a central canal? |
no |
|
what are circumferential lamellae? |
rings of bone that run the entire circumference of the bone shaft |
|
What creates the circumferential lamellae? |
periosteum |
|
What is ossification? |
formation and growth of bone tissue |
|
What are the two types of ossification? |
intermembranous endochondral |
|
What is the pre-existing tissue in intramembranous ossification? |
mesenchyme |
|
What is the pre-existing tissue in endochondral ossification? |
hyaline cartilage |
|
What are the 4 main steps of intramembranous ossification? |
1. ossification centers form 2. osteoid undergoes calcification 3. woven bone and surrounding periosteum form 4. lamellar bone replaces woven bone |
|
What happens to the mesenchymal cells in the first step of intramembranous ossification? |
they turn into osteoblasts that secrete osteoid |
|
What happens in the second step of intremembranous ossification? |
Calcification of osteoid |
|
what is calcification |
minerals are deposited in osteoid |
|
What happens to the osteoblasts once they are calcified? |
They become osteocytes |
|
What happens in step 3 of intramembranous ossification? |
Woven bone forms |
|
What happens in the final step of intramembranous ossification? |
lamellar bone replaces woven bone |
|
What is lamellar bone? |
mature bone |
|
What are the 6 steps of endochondral ossification? |
1. fetal hyaline cartilage model of bone develops
2. cartilage undergoes calcification 3. primary ossification center forms in diaphysis 4. secondary ossification centers form in epipyses 5. bone replaces cartilage 6. epiphyseal plates ossify |
|
What happens in the first step of endochondral ossification? |
fetal hyaline cartilage model bone develops |
|
What happens in the second step of endochondral ossification? |
cartilage calcified and periosteal bone collar forms |
|
During the second step of endochondral ossification, what happens to chondrocytes? |
they enlarge within the shaft and resorb part of the cartilage |
|
During the second step of endochondral ossification, what happens to the cartilage after it is resorbed? What happens to the chondrocytes that resorbed it? |
It undergoes calcification Chondrocytes die leaving a hardened matrix |
|
What is happening in the perochondrium during the second step of endochondral ossification? |
it is invaded by blood vessels cells in perichondrium turn to osteoblasts |
|
In the second step of endochondral ossification, what is the periochondrium turned into? |
periosteum |
|
What happens in the third step of endcochondrial ossification? |
primary ossification center forms in the diaphysis |
|
What replaces the calcified cartilage in the third step of endochondral ossification? |
bone |
|
What is the fourth step of endochondral ossification? |
secondary ossification centers form in epiphyses (ends of long bones) |
|
What happens in the fifth step of endochondral ossification? |
bone replaces cartilage, except the articular cartilage and epiphyseal plate |
|
What is the epiphyseal plate responsible for? |
bone growth (length) |
|
Approximately how long is the epiphyseal plate active? |
15-25 years |
|
What is the sixth step in endochondral ossification? |
epiphyseal plates ossify and form epiphyseal lines |
|
what is an epiphyseal line? |
thin plate of compact bone between the epiphysis and diaphysis |
|
What is bone remodeling? |
continuous deposition of new bone tissue and removal of old bone tissue throughout one's life |
|
Which statement is TRUE about endochondral bone growth? A. bone replaces an areolar connective tissue model B. New bone is created by osteoclasts C. The epiphyseal plate is responsible for lengthwise bone growth D. when blood vessels invade the model of the bone, the periosteum changes into the periochondrium E. the epiphyseal plate remains active throughout a person's life |
C. the epiphyseal plate is responsible for lengthwise bone growth |
|
What is the region of bone between the diaphysis and epiphysis? |
metaphysis |