HLTH: review of muscle and integumentary Flashcards
what is the function of unique markings on bones?
to provide an attachment site for tendons or for the passage of nerves and vessels
functions of bones
movement, protection for the viscera, and metabolic storage of calicum
bone matrix
collagen fibres and calcium phosphate salts (hydroxyapatite)
dynamic equilibrium of bone
osteoblasts produce new bone and osteoclasts degrade bone
what is the bone stem cell and where is it derived from?
osteoprogenitor cells which are derived from embryonic mesenchymal cells
what do osteoprogenitor cells divide into?
osteoblasts
osteoblast function
secrete new bone matrix
what do osteoclasts come from?
macrophage progenitor cells
osteoclast function
resorption of bone tissue
two types of bones
compact and spongy
spongy bones
less dense and form the interior structure of bones; these lack haversian systems
epiphyseal plate
is the site of longitudinal bone growth and this is promoted by growth hormone and sex hormones
epiphyseal line
is the epiphyseal plate in adulthood once growth ceases; this stops when the epiphyseal plate ossifies
what kind of CT is articular cartilage?
hyaline cartilage
hormones that change bone density?
growth hormone, PTH, or cortisol
osteoporosis
the loss of bone density caused by loss of calcium salts; common in older women
what is the bone covered with?
periosteum which is a fibrous CT; it is also covered by articular cartilage at tips of bones
what does the periosteum contain?
osteoblasts, blood vessels, nerves, and lymphatics
what is the medullary cavity lined with?
endosteum that contains osteoblasts
where is red bone marrow found?
the cranium, vertebral bodies, ribs, sternum, and ilia
four basic functions of skeletal muscle
to facilitate body movement by muscle contraction, to maintain body position by muscle tone, to stabilize the joints and prevent excessive movement, and to maintain body temperature
involuntary skeletal muscle movement
occurs for respiratory movement, postural reflexes, blinking, shivering, or certain facial expressions
what creates striated appearance?
the arrangement of actin and myosin filaments within the muscle fibres
3 muscle layers
epimysium, perimysium, and endomysium
epimysium
surrounds the entire muscle
perimysium
surrounds the muscle fascicles
endomysium
surrounds the individual muscle fibres (cells)
motor unit
is the motor neuron of the spinal cord and all the muscle fibres it stimulates
neuromuscular junction
is where the synapse between the end of the motor nerve and the receptor site in the muscle fibre is located
what neurotransmitter is released for muscle contraction?
acetylcholine
acetylcholinesterase
is the enzyme that inactivated ace
myofibrils
each muscle cell contains this and it is made up of smaller myofilaments consisting of actin and myosin filaments
blood vessels during exercise
are dialated to promote greater blood flow into the muscle, thus increasing the supply of O2 and nutrients to provide energy for contraction
myoglobin
is stored in muscle fibres and can store limited amounts of O2
where is glycogen stored?
in muscle
aerobic respiration
produces ATP for muscle fibres as long as O2 is made available from the myoglobin