1st semester: Muscle Physiology Flashcards
TRUE about the A band
the lateral edges are formed by ends of thick filament
the physiological property unique to muscle cells is due to the presence of
organized myofilaments
when acetylcholine acts on the end-plate, it will initially affect activity of the
voltage gates CALCIUM channels
what happens when ATP binds to the myosin head?
there is cross bridge formation
TRUE about the spatial and temporal summation
results to an increase in force of contraction
an applicant in athletics practiced for 4 hours when he complained of inability to continue further and cannot continue the mechanical event. What case is this most likely?
Fatigue due to high levels of lactic acid in the sarcoplasm
Maximum tension is generated by an activated muscle if the sarcomere length is _____
Ideal (resting) length
Reconstitution of energy stores after contraction (exercise) results to body heat production known as _____
Recovery heat
When a skeletal muscle attains maximum work and it was given
decrease work performed
This characteristic is associated with cardiac and skeletal muscles but NOT in smooth muscle
Their contraction is thin filament regulated
Primary function of sarcalumenin in muscles
transport Ca++ from the uptake site to the release site
When the skeletal muscles contract and was able to carry a lighter load to a greater distance, it is performing
Isotonic concentric contraction
The absolute refractory period of the muscle twitch is during the
LATENT period
SERCA 2 are used by this type of muscle fiber
type 1
TRUE regrading the sarcotubular system of skeletal muscles
contains the receptors acting as Ca++ channels
A series of sarcomeres form the ____.
myofibril
Which activity is happening during the latent period of the muscle twitch?
Inhibition of ligand gated ion channels in the end plate
TRUE of regarding activity of skeletal muscle
Heat production in a muscle is observed even if it is resting
The ff. physiological events immediately precedes the generation of AP during excitation-contraction coupling in skeletal muscle?
generation of END PLATE POTENTIAL
Immediately after the release of phosphate from the myosin head, the muscle fiber in ____
power stroke state
Which activity is happening during the relaxation period of the muscle twitch?
UTILIZATION of ATP
Location of the transverse tubules in skeletal muscle responsible for formation of “triad” is
A-I junction
a 21 year old medical student is an avid body builder who lifts weights approximately 2-3 hours per day. Which of the following BEST describes the latent phase of his muscle twitch during work out?
Requires the mechanical activation of calcium channels attached on the cisterns
Urinary smooth muscle communicate _____
electrically
