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16 Cards in this Set

  • Front
  • Back
___= outer cell membrane

___= inside of a muscle cell (fiber), has elongated protein strands

___= smooth, endoplasmic reticulum, fills the clefts/spaces btw myofibrils

Sarcolemma forms tubular invaginations known as _____(transverse systems) which propogate action potential to inside of the cell
sarcoplasmic reticulum

t- tubule
___= segment of myofibril btw adjacent z lines ( the fundamental unit of contraction in striated muscle)

__- thick filament composed of these molecules, shaped like a gold club

___= thin filament composed of these moleculular proteins


___= middle light section that closes during contraction

___= line down the middle of the sarcomere, vertically
h zone

M line
___= excitatory synapse

___= openings that allow sodium ions to enter the cell
neuromuscular junction

ligand-gated membrane channels
Without ____, muscle cannot relax
____= ADP + phosphoric acid+energy (for immediate use in contraction)

___= Creatine+phosphoric acid+energy (for resynthesis of ATP from ADP)

___= lactic acid+energy(for resynthesis of CP from creatine and phosphoric acid)

___= water+carbon dioxide+ energy (for resynthesis of ATP and CP)
ATP- adenosine triphosphate

CP-creatine phosphate


Lactic acid and oxygen
____= condition caused by neurotoxin clostridium tetani, excitatory pulses arent regulated, produces continuous tonic muscle spasms, lockjaw
___= toxin produced by clostridium botulinum, acts on neuromuscular junction, toxins prevent vesicles containing ACh at the synapse from releasing, causes paralysis due to lack of muscle contraction
___= when most ATP is depleted-myosin heads cant seperate from actin, and calciu, cant be taken back into the SR by calcium pump= no relaxation, continuous contracted state...
___= this condition upon death

rigor mortis
___= decrease in ATP availability, affects muscle cell and not due to neurons, increase in lactic acid
__= energy used immediately in contractions

___= energy used for resynthesis of ATP from ADP

___= for resynthesis of CP from Creatine and phosphoric acid

___= for resynthesis of ATP and CP...used last



lactic acid and oxygen
How is calcium important to muscle contractions. What happens if calcium is not reabsorbed.
Calcium binds to the troponin of the actin after being released from the SR causing muscle contraction. For the contraction to end, calcium has to be trasported back into the SR by the calcium ATPase pump. This reduces concentration of calcium in myofibril area, so calcium dissociated from troponin andtropomyosin then again covers the myosin connecting point on the actin and muscle relaxes. If it doesnt absorb, it keeps conracting.
How do myosin and actin interact during a muscle contraction.
When the calcium binds to the troponin, it cause tropomyosin to reveal the myosin binding sites of the myosin heads on the actin. Myosin and actin stay attached until the action potential has stopped and calcium levels are back to normal.
Binding of the myosin head to actin leads to the release of____ & ___.
ADP and phosphate which were bound to the myosin head
When ATP is used up, ____ is used (normally abt 5x as much as ATP), to replenish ATP. If muscle contraction lasts longer, and uses up CP too, ____ is obtained from the blood supply, and the glycogen stored in the muscle fibers, and to complete the cycle _______ and oxygen are needed.
lactic acid