Muscle Tissue Flashcards
It is characterized by the ability to contract or move upon stimulation.
Muscle Tissue
Muscle tissue is characterized by the ability to ________ or move upon stimulation.
contract
Muscle tissue is composed of specialized cells that optimize the universal property of ___________.
contractility
The muscle cells are of ____ origin.
mesodermal
Muscle cells differentiate by a gradual process of ________.
cell lengthening
Muscle cells differentiate by a gradual process of cell lengthening and abundant synthesis of __________.
myofibrilar proteins (actin and myosin)
Two contractile proteins
Actin and Myosin
Movement is generated through the interaction of _________.
Actin and Myosin
It is the cytoplasm of the muscle cells.
Sarcoplasm
It is the smooth endoplasmic reticulum of the muscle.
Sarcoplasmic Reticulum
It is the cell membrane and external lamina of the muscle.
Sarcolemma
Which Muscle Type?
Multi-nucleated cells
Skeletal Muscle
TRUE OR FALSE.
Skeletal muscle LACK cross-striations.
False
Which Muscle Type?
Quick, forceful, voluntary contractions
Skeletal Muscle
Which Muscle Type?
Branched cells bound to one another
Cardiac Muscle
Which structure is responsible for joining two structures together in a cardiac muscle?
Intercalated discs
Which Muscle Type?
Involuntary, vigorous, and rhytmic contractions
Cardiac Muscle
Which Muscle Type?
Fusiform cells with no striations
Smooth Muscle
Which Muscle Type?
Slow, involuntary contractions
Smooth Muscle
Other names for skeletal muscle
Voluntary or Striated Muscle
Which is responsible for the striations of skeletal muscle?
Actin and Myosin
It is responsible for the movement of skeleton.
Skeletal Muscle
It is responsible for the movement of organs such as the globe of the eyes, and tongue.
Skeletal Muscle
It consists of muscle fibers, which are long, cylindrical, and multi-nucleated cells.
Skeletal Muscle
Diameter of skeletal muscle
10 - 100 um
During ________, mesenchymal myoblasts fuse, forming myotubes with many nuclei.
embryonic muscle development
During embryonic muscle development, ________________ fuse, forming myotubes with many nuclei.
mesenchymal myoblasts
During embryonic muscle development, mesenchymal myoblasts fuse, forming ________ with many nuclei.
myotubes
They proliferate and produce new muscle fibers following muscle injury.
Satellite Cells
They also originated from myoblasts, but failed to differentiate nor fuse.
Satellite Cells
Which type of tissue is present in all types of muscle?
Connective Tissue
The layers of connective tissue is seen well in ___________.
Skeletal Muscle
An external sheath of dense irregular connective tissue, which surrounds the entire muscle.
Epimysium
Which kind of connective tissue is present in the Epimysium?
Dense Irregular
TRUE OR FALSE.
The epimysium carries large nerves, blood vessels, and lymphatics.
True
A layer of thin connective tissue that immediately surrounds each bundle of muscle fibers (fasicle).
Perimysium
The nerves, blood vessels, and lymphatics penetrate the ____ to supply nutrient to each fasicle.
Perimysium
Which type of connective tissue is present in the Perimysium?
Thin Connective Tissue
It contains a delicate layer of reticular fibers surrounding the external lamina of individual muscle fibers.
Endomysium
Which type of connective tissue is present in the Endomysium?
Reticular Fibers (tissue)
A layer of dense irregular connective tissue overlying the epimysium.
Deep Fascia
Which type of connective tissue is present in the Deep Fascia?
Dense Irregular
All of the interstitial tissue are met (joined) by ________.
Myotendinous junctions
Dark bands are called _______.
A or Anisotrophic Bands
Light bands are called _______.
I or Isotrophic Bands
________ is highly organized, containing primarily long cylindrical filament bundles called myofibrils.
Sarcoplasm
Sarcoplasm is highly organized, containing primarily long cylindrical filament bundles called _________.
myofibrils
Which band is bisected by a Z disc?
Isotrophic Band
It bisects the isotrophic band.
Z Discs
The repetitive functional (structural) unit of striated muscle.
Sarcomere
________ extends from Z disc to another Z disc.
Sarcomere
It transmits mechanical process along the interstitial connective tissue.
Collagen
Components of Thick Filaments
Myosin
Thick filaments are found on the ________.
A band
Components of Thin Filaments
- F-actin
- Troponin
- Tropomyosin
Thin filaments are found on the ________.
I band
Two Regulatory Proteins
Troponin and Tropomyosin
What are the 3 subunits of Troponin?
- Trop I (TnI)
- Trop C (TnC)
- Trop T (TnT)
A subunit that regulates actin-myosin interaction.
Trop I (TnI)
A subunit that binds calcium.
Trop C (TnC)
A subunit that attaches to tropomyosin.
Trop T (TnT)
It contains the binding site for myosin.
G-actin
When myosin heads bind to g-actin, it forms __________.
transcient cross bridges
____ catalyzes energy release when myosin head binds to g-actin.
ATP
_____ consists of the portion of the thin filaments which do not overlap the thick filaments in the other band.
I bands
_____ contain both thick filaments and overlapping portions of thin filaments.
A bands
Why are A bands darker?
Because they contain both thick filaments and overlapping portions of thin filaments.
It binds thin filaments anchored to Z discs.
Alpha-actinin
It binds thick filaments anchored to Z discs.
Titin
The largest protein in our body which has a scaffholding and elastic properties.
Titin
The lighter zone located in the center of each A band or sarcomere.
H zone
It bisects the H zone.
M line
M line contains ______.
Myomesin
A myosin-binding protein
Myomesin
It holds the thick filaments in place.
Myomesin
Myomesin contains the enzyme _______.
creatine kinase
It catalyzes the transfer of phosphate groups.
Creatine Kinase
A storage for high-energy phosphate, which can be transferred to ADP when ATP is utilized.
Phospho-creatine
The soul for muscle contraction.
ATP
It functions in Ca2+ sequestration during muscle contraction.
Sarcoplasmic reticulum
They trigger the release of Ca ions.
Triad - Transverse Tubules (T-tubules) and Terminal Cisternae
Long, fingerlike invaginations of the cell membrane encircling each myofibril near the aligned A- and I-band
Transverse Tubules
These are expanded structures adjacent to each T-tubule.
Terminal Cisternae