Chapter 16: Skeletal System Flashcards
What are structural function of bone? physiological functions?
support/ locomotion/ protection
Hematopoiesis (site for blood cell formation)
immune function (white blood cells)
storage house of Ca2+, phosphate allow nerve conduction, heart/muscle contraction, energy formation, blood clotting
What are types of bone in body?
axial (skull, vertebrae columns, rib cages) and appendicular (hands, hip, legs - extremities)
What is bone tissue?
Osseous tissue
Bone Remodeling?
the continual breakdown of bone tissue (resorption) and new deposit of bone (formation)
What cause the decrease (-) / increase (+) in bone formation?
mechanical loading (+) PTH, Vitamin D (+)
What cause the decrease (-) / increase (+) in bone resorption?
Disuse of bone (+)
Estrogen (-)
Vit D, PTH (+)
What cause the increase in calcium ingestion and absortion?
Vit D, PTH, Estrogen
What cause calcium filtration/ reabsorption of kidney pathway
calcium filtration: vitamin D synthesis calcium reabsorption (+) PTH and estrogen
What is the unit of bone? What does it have
Osteon (arteries and veins)
What are bone tissue types?
cortical and trabecular
Characteristic of cortical
compact, dense, lamelae network surrounded by cell
characteristic of trabecular bone tissue
spongy, porous, latticelike network
easily fractured and models more rapidly due to large surface area
What type of tissue bone has the greatest loss of BMD?
trabecular bone tissues
What type of bone tissue does axial bones most? appendicular bone?
trabecular
cortical
What are type of growth in bone?
appositional: growth in mass (thickness)
longitudinal: growth occurs at epiphyseal until adult stature
What is bone modeling? How does this occur?
the process of altering shape of bone via the bone resorption and formation
due to injuries, break
What are the bone cells types?
osteoblast, osteoclast, osteocytes
What does the osteoblast do?
bone resorption, secrete enzymes that degrade bone matrix
What does the osteoclast do?
bone formation, produce organic matrix, calcifies and hardens as minerals deposited
What is osteocyte? What does it do?
the mature osteoblasts, covered by the calcified bone
regulate process of remodeling
What are the purposes of remodeling bone?
turnover, maintenance, repair, replacement
What is osteoid?
the uncalcified matrix that secreted by osteoblast
Is there evidence that young athlete has greater bone growth than sedentary youngsters?
NO
what are mechanical factors influence BMD?
Gravity and physical activities (weight-bearing exercises)
What are the measurement techniques for BMD? Which one is better?
DEXA and QCT
QCT
What is the best about QCT?
It separates cortical and trabecular bone
No error for spine degenerative or aortic calcification
Give info about bone morphometry
provide true volume density unit mg/cc
What is good about DEXA?
low dose of radiation and price
What are the factors of bone development?
nutrition, genetics, hormones, physical activities
what is minimal effect strain?
the minimal stress exercise on bone that allow BMD increase
when astronaut land on earth (with gravity) which cell of bone are most active?
osteoclasts
How many % an healthy adult recycle their bone mass?
5-7%
What bone is suited for physiological function? why?
trabecular because they are easiest broken down and released to blood
what is osteoporosis? What population it affect most? Where does injury occur most in osteoporosis
the disease in which bone become more fragile and easily fractured
woman
wrist, spine and hip
What race has more risks of osteoporosis?
black
How many times woman has more risks of osteoporosis than man?
4 times
What nutritional factors that cause the risk of osteoporosis?
Calcium
Alcohol increase risk
Protein intake cause loss of Ca2+ in urine
Is static resisting exercise better than dynamic exercise in maintain health bone?
No, dynamic exercise is better
How is the rate of bone loss between woman and man?
they are the same although man has more bone mass than man
How is BMD affected in female athlete?
Decreased Ca2+ level due to low energy availability
What does lower energy availability in female athlete led to?
skeletal demineralization
dysfunction menopause
What does stress fracture happen?
when stress reactions not occur to repair degeneration of joint capsule
What is the physiological change in amenorrhea that affect BMD?
hormones (estrogen) deficiency
How is microtrauma and macrotrauma different?
in length of recovery but mechanism is the same
