MUSCLE TISSUE Flashcards
Striated; alternating dark and light bands
Striations of skeletal muscle
Multi-nucleated at periphery
Is the nucleus of skeletal muscle single or multinucleated? And where it can be found?
Rapid and voluntary
What is the contraction of skeletal muscle?
Myofibrils
What are the main component of sarcoplasm?
Pushed by the myofibrils
Why are the nuclei of the skeletal muscle are at the periphery?
Nonstriated; nonbranching
Is the smooth muscle striated or nonstriated? Branching or nonbranching?
Fusiform/ spindle-shaped/ squamous
Shape of the cells in smooth muscle
Single and center
Smooth muscle
Nucleus: mono/multinucleated? Periphery/center?
Homogenously eosinophilic (red/pink stained)
What is the condition of the smooth muscles’ cytoplasm?
Involuntary and slow
Contraction of smooth muscle?
Striated; branching
Cardiac muscle
Striated/non striated?; branching/nonbranching?
Mononucleated; center
Cardiac muscle
Nucleus: multi/mono-nucleated? Center/periphery?
Involuntary and rhythmic
What is the contraction of cardiac muscle?
Intercalated disk
In cardiac muscle, what makes the cell join together?
Muscle Fascicle Muscle fiber Myofibrils Myofilaments
Organization of skeletal muscle from macro to microscopic
Dense connective tissue
What is the kind of CT that epimysium is made up of?
Surround the muslce
What does epimysium covers?
Thin and branching CT
What is the CT of the perimysium?
True
True/false: In perimysiun there is the presence of blood vessels and nerves
Fascicle
What does perimysium surrounds?
Muscle fiber
What does endomysium surrounds?
Delicate network of reticular fibers
What is the composition of endomysium?
Myofibril
It is the main bulk of muscle fiber
A band
Dark band of myofibril that consist of alternating thin and thick filaments
False
True/false: A band also shortens during contraction
H band
Central portion of A band; devoid of thin filaments
M line
Bisect H band
I band
Light band; devoid of thick filaments
I band
It is the one that shortens during contraction (myofibril)
Z line
Bisects I band
Center: A band: 2 contiguous I bands one on each side
The sarcomere includes centrally located _________ and 2 ________ contiguous __________ one on each side
Sarcomere
It is the basic contractile unit that is located from one Z line to another Z line
M line to Z line
The boundary of extension of the titin (from __ line to __ line) - myofibrils
Titin
It maintains location of A band; responsible for the ability of muscle to back into its resing length after being stretched
A bands I bands Z lines
These myofibrils are the only ones that can be seen under LM
Sarcolemma
Plasma membrane of the muscle
External lamina
What is the coating of the external surface of sarcolemma
Dystrophin
It is the coating of the inner layer of sarcolemma that prevent muscle cells from being stressed due to continuous stretching
Muscular dystrophy
A hereditary disease caused by a defect in the gene for dystrophin
Males (9-13 years)
Who are affected by the muscle dystrophy?
Satellite cells/myosatellite cells
Precursors of skeletal muscle cell that is found underneath the sarcolemma
External lamina
What should be kept intact for the continuous regeneration of satellite cell?
Mitochondria
What is the organelle that is called sarcosome in muscle tissue?
Sarcoplasm
It contains glycogen granules and myoglobin
Glycogen granules
It contains the energy needed for muscle contraction
Myofibrils
Oxygen binding protein of skeletal muscle tissue that gives its brown color
Sarcoplasmic reticulum
A site for sequestering calcium during muscle relaxation
False
True/false: there is the presence of ribosomes in sarcoplasmix reticulum
Terminal cisterna
Found at A-I junction that contains calsequestrin
Calsequestrin
Protein that sequesters Calcium
T-tubule
Found at each pair of terminal cisterna that is a tubular invagination of the sarcolemma extending inward from the surface of the fiber
T-tubule
It is the passageway of action potentials from sarcolemma
Triad
2 parallel terminal cisterna + T-tubule is called?
Two triads
Each sarcomere is composed of how many triad?
It aids in muscle contraction
Function of triad
False - it is the only thick filament
True or false: Myosin is a thin filament
Myosin
A protein that is a major component of the A band
Heavy meromyosin
Light meromyosin
These two results from the division of myosin due to enzymatic cleavage
Heavy meromyosin
It comprises the head and forms the cross bridge (Myosin)
Cross bridging
It happens when the head goes toward actin when muscle contracts
False
True/false: Crossbridge is found in H band
Light meromyosin
It comprise the tail of the myosin
Actin
Tropomyosin
Troponin
Proteins that composed the thin filaments of myofilament
Actin
Protein that is the main component of I band
Polymerization of G-actin
This process results to one strand of actin
F-actin
It is a two stranded actin (2 helically entwined strands)
G-actin
It is the binding site of myosin to actin are located
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