Discussion 2 Notes Flashcards
______________ greater length change, force remains the same
sarcomere in series
__________________ greater force production. Length change is only 20nm
sarcomere in parallel
_______________is the change in length of 1 sarcomere in series
20 nm
___________ is a function of the number of working cross bridges per half sarcomere.
force
How can you create more force
more overlap, More cross bridges, more force produced
what are the 3 ways to generate force
- optimize sarcomere length
- Increa Ca2+ via neural input
- Increase sarcomeres or muscle in parallel
Chad wants to get big and lift heavy he should
get more sarcomeres in parallel
Chad does not want to wait long what should
- optimize sarcomere length
- modify neural input
________ is determined by muscle stiffness.
passive tension
passive tension is a resistance to _________________ in structure
deformation or conformational change
passive tension increase as we pass ________________
resting length of sarcomeres (2.1 μm)
What is the extracellular component of muscle stiffness
collagen
what is the intracellular component of stiffness
titan
titan Spans
whole half of sarcomere
Length tension curve:
V max for muscle unload muscle until
3.6 μm
Length tension curve
velocity decreases as you increase the
after load
- weight is opposing the force produced by cross bridges
- velocity when after load is f max-1.6 max
- negative velocity in the opposite direction you want (muscle lengthening)
Velocity decreases as you increase
muscle length because longer muscle from Manuel stretching and less cross bridges are available
what Are the 3 types of contraction
- concentric
- Isometric
- eccentric
_____________ a muscle shortens while contracting (+v)
concentric
_____________ a muscle doesn’t change length while contracting (v-=0)
isometric
__________ muscle lengthens while contracting (-v)
eccentric
_________________ process of electrical stimulation (AP) initiation muscle contraction via triggering of intracellular Ca 2++ release
excitation of contraction coupling (ECC)
Where is excitation of contraction coupling initiated
at neuromuscular junction (NMJ)
______________ is the postsynaptic membrane of a muscle fiber
sarcolemma
what covers the sarcolemma
basement membrane
___________ is a NMJ receptor on muscle fiber membrane that is a ligand gated NA channel
ACHR
_____________ are NMJ receptors located all over sarcolemma
violtage gattet sodium channels
___________________ on sarcolemma basement membrane. Breaks down acetylcholine to stop exciting muscles
ACHE
___________ specializations in my-fiber membrane (sarcolemma) to rapidly propagate Ca 2+.
T tubules
T tubules wrap around what
the myofibrils
____________ is rich in CA2+ storage.
Sarcoplasmic Reticulum
How is calcium let out of the SR
RYR receptors
SR uses _________ on its membrane to pump calcium against its concentration gradient
calcium pump
__________ link the T tubules and the SR
feet link
What is involved in bringing calcium from T tubules to VG ca channels
DHP R
What is involved in bringing calcium from the sarcoplasmic reticulum to the calcium gated channels
RYR receptors
what are the steps of the excitation event
- depolarize NMJ via presynaptic signal
- synaptic Ach vesicle five with presumaptic membrane and can release ACH
- ACh binds to AchR
- AchR opens to let the NA center muscle fibers. Ache hydrolyze Ach after it bound to close ACHR and stop NA flow
- T tubule depolarizes
- DHPR opens which mechanically opens RYR
- Calcium release from SR
- Calcium Pump is maintained
- muscle contracts
__________ G actin, troponin, tropomyosin
Thin filament
____________ mhc, mlc
thick filament
_________ binds ot calcium
TNC
____________ inhibits binding of MHC
TnI
__________ binds tropomyosin
TnT
Ca and cross bridge explained
- Ca binds to TNC
- TNC has conformation, rolls troponin complex toward groove by G actins
- binding site MHC head is exposed, mhc head bi ending to G actin. This is amplified Ca2+ binding
- by moving, troponin complex. More of 1 tropmysin to exposed 7G actin this amplified CA 2+ binding
- Increasing frequency of depolarization
____________ phosphatecronin PG gives up high energy bond to make ATp
. Catalyzed by creatine phosphokinase , can be rephosphorylated, good for abrupt intense work
high energy phosphate system
aerobic metabolism.
Glycolysis. Breakdown of glucose in glycogen form to produce ATP. Last no O2 and low yield 2ATP rapidly repeated
aerobic metabolism
-slow requires o2. high yield, 3 Atp
good for endurance
