Physiology Final Exam correctly
answered to pass
The tendon is responsible for... - correct answer ✔✔Keeping the skeletal muscle attached to the bone
The tendon is made up of connective tissue at what three layers? From smallest to largest groupings. -
correct answer ✔✔(1) Endomysium
(2) Perimysium
(3) Epimysium
What regulates protein synthesis throughout the muscle cell? - correct answer ✔✔Myonuclei
What type of cells assists in repairing muscle damage? - correct answer ✔✔Satellite Cells
The Isotropic Band (I Band) of the sarcomere is composed of... - correct answer ✔✔Thin Filaments
Titin
Z disk
The A Band of the sarcomere is composed of... - correct answer ✔✔Thin Filaments
Thick Filaments
The H Zone of the sarcomere is composed of... - correct answer ✔✔Only the thick filament without the
myosin heads
During contraction of the sarcomere, what change occurs in the thin and thick filaments? - correct
answer ✔✔The amount of overlap between the two
,The SR is responsible for... - correct answer ✔✔The storage and release of Ca++
How does each myofibril have access to the extracellular fluid? - correct answer ✔✔Via the T tubules
Dihydropyridine Receptors (DHPR) are found in the __________ and they are ________ receptors -
correct answer ✔✔T tubule ; Voltage
Ryanodine Receptors (RyR) are found in the _______ and they are _______________ channels. - correct
answer ✔✔SR ; Calcium Release Channels
The thick filament's molecular structure is composed of what 2 things? - correct answer ✔✔(1) Myosin
(2) Titin
F-actin in the thin filament is... - correct answer ✔✔A helix of globular G actin that exposes an active site
in which the myosin head can bind to
Tropomyosin is a single strand protein that... - correct answer ✔✔Covers the active site fount on F-actin
The troponin complex in the presence of Ca++ can... - correct answer ✔✔Move tropomyosin to expose
the active site of F-actin
CapZ anchors _______ to the ___________ of the sarcomere - correct answer ✔✔Actin ; Z-disk
Dystrophin connects the sarcomere to the _______ & __________. Without it there would be significant
cell damage during contraction - correct answer ✔✔Extracellular fluid; Sarcolemma
The presynaptic membrane contains what two things? - correct answer ✔✔(1) Mitochondria
(2) Acetylcholine Vesicles
What happens during the activation of the presynaptic membrane? - correct answer ✔✔Acetylcholine
vesicles fuse and release their contents into the synaptic cleft
, As acetylcholine diffuses across the synaptic cleft, it binds to ___________. What does this binding lead
to an activation of? - correct answer ✔✔Nicotinic Receptors ; Increased Na+/K+ permeability
Standard activation of nicotinic receptors causes? - correct answer ✔✔A shift in membrane potential (-
80mV ——> -15mV)
What are the 3 phases of excitation-contraction coupling? - correct answer ✔✔(1) Action Potential
Propagation
(2) Ca++ Release
(3) Exposure of Actin Active Sites
During action potential propagation, the action potential reaches the triad which leads to... - correct
answer ✔✔Activation of the voltage sensitive DHPR in the T-tubule which opens the RyR in the SR to
release Ca++
Activation and Release of Ca++ happens in these 4 steps... - correct answer ✔✔(1) Membrane
Depolarization
(2) Mechanical Coupling between DHPR & RyR
(3) Ca++ exits SR
(4) Ca++ entering cell via DHPR also activates Ca++ release channels
Halothane was an anesthetic that physicians stopped using because it would... - correct answer ✔✔Bind
to RyR causing chronic muscle activation
Caused malignant hyperthermia & sustained contractions that would raise an body temp to system
failure levels
What are the 4 phases of Cross-bridging Cycle? - correct answer ✔✔(1) Binding- myosin binds to actin
(2)Power Stroke- myosin head swivels, ADP+Pi are released from myosin.
(3) Dissociation- ATP bind to myosin; actin and myosin dissociate
(4) Activation- Energy from the hydrolysis of ATP is used to activate myosin head