musculoskeletal system Flashcards
skeletal muscle
how we move, maintain posture, temp, guard and support our body
3 layers of skeletal muscle
epimysium, perimysium, endomysium
number of skeletal muscle
700
cardia muscle tissue
found only in the heart
timing of contractions controlled by pacemaker cells
aerobic metabolism
impossible to tetany
contractions are 10x longer than skeletal muscle
smooth muscle tissue
found lining organs
sphincters regulate movement
contracts are the longest
fast fibers
majority of fibers, fatigue more rapidly, fast use of ATP
slow fibers
slower to fatigue, more o2 supply, more mitichondria
white muscles
where fast fibers live
red muscles
where slow fibers live
anaerobic endurance
length of time contractions are supported by energy reserves such as ATP
aerobic
length of time a muscle can contract while being supported by breakdown of carbs, lipids, acids
rigor mortis
around 6 hours after death, glucose/energy is depleted, sustained contractions
muscular dystrophy
abnormality of the gene
pregressive muscle weakness
myasthenia gravis
autoimmune disease. weakness/fatigue
rhabdomyolysis
unconscious/immobile, prolonged time, muscles is destroyed, dark red urine, kidney failure
fascia
surrounds every muscle and may form cordlike tendons beyon each muscle’s end
aponeuroses
broad sheets of fibers that may attach to bones or to the coverings of other muscles
epimysium
a layer of connective tissue that closely surrounds skeletal muscles
perimysium
another layer that seperates muscle into small compartments
muscle fasciulus
bundles of skeletal muscle cells inside perimysium compartments which are bound togeter by connective tissue
endomysium
layers allow for independent movement
skeletal muscle fiber
single cell that contracts and relaxes in response to stimulation
sarcolemma
cell membrane surrounding each muscle fiber
contraction of skeletal muscles
contract when organelles and molecules bind myosin to actin to cause a pulling action.
adenosine triphosphatase (ATPase
causes the breakdown of atp to both adenosine diphosphate and phosphate releasing energy
acetylcholine
the neurotransmitter that stimulates skeletal muscle to contract
muscle relaxation
occurs when calcium is actively transported back into the sarcoplasmic reticulum
recovery period
oxygen debt after exercise. heavy breathing until oxygen is supplied to the muscles
after exercise oxygen is required to…
metabolize lactic acid. replenish atp, phosphocreatine, and glycogen. pay back any oxygen that has been borrowed from hemoglobin and myoglobin
oxytocin
hormone that stimulates contraction of smooth uterine muscles
for an action potential to occur
a polarized cell is needed
action potential
a rapid, transient change in the electrical potential of a cell membrane, primarily in neurons and muscle cells, that serves as a fundamental unit of communication and signaling in the nervous system and other excitable tissues.
polarized cell
a cell at rest, waiting to react to a stimulus
