Muscles Flashcards
What are the three types of muscle
Skeletal
Cardiac
Smooth
Which type of muscle is voluntary?
Skeletal
Which type of muscle is involuntary?
Cardiac & smooth
Where is smooth muscle found?
In the organs
Smooth muscle is striated/nonstriated?
Nonstriated
Smooth muscles are _______ in shape
Fusiform
Cardiac muscle is only found where?
In the heart
Cardiac muscle is striated or nonstriated?
Striated
Cardiac cells are _______ elongated fibers
Branching
The ______________ are found where the cell membranes come together in gap junctions
Intercalated disk
Skeletal muscle is found where?
In the muscles of the limbs and trunk
Skeletal muscle is striated/nonstriated?
Striated
Skeletal cells are _________ in shape
Long cylinders
__________ contains multiple peripheral nuclei
Skeletal muscle
What are the three types of skeletal muscle coverings?
Endomysium
Perimysium
Epimysium
__________ go around each cell and is loose connective tissue
Endomysium
__________ surround each fascicles and are connective tissue
Perimysium
_______ surround each muscle and are dense connective tissue
Episysium
If you increase the diameter of the fascicle, you __________ the control of the muscle
Decrease
What are the 4 components that make up a sarcomere
M-Line
H-zone
A-band
I-band
The functional unit of muscle contraction (from Z-line to Z-line)
Sarcomere
Thick filaments are held together by ________ ___ _________
Nodes of protein
Where nodes are located
M-line
Defined by the ends of thin filaments
H-zone
End of thick filaments, overlaps with thin
A-band
Only thin filaments are located here
I-band
Very concentrated thin filaments
Z-line
What is the ratio of thick to thin filaments?
1 thick : 6 thin
What are the 3 components of thin filament?
Actin
Tropomyosin
Troponin
Two Long strand of F-actin (made of G-actin) twisted together
Actin
Glue that holds F-actin strands together
Tropomyosin
What are the three subunits or troponin?
TnT
TnC
TnI
What is the function of TnT
Bind to tropomyosin
TnC function
Binds calcium
TnI function
Blocks interaction between actin and myosin (keeps muscles from contracting all the time)
Thick filaments is made of what?
Myosin
What are the two subunits of myosin?
Heavy meromyosin
Light meromyosin
What is the function of heavy meromyosin?
Forms head of molecule - has binding sites for ATP and actin
Which type of skeletal muscle is related to continuous slow contractions?
Type 1
Type 1 muscle fibers are rich in ______
Myoglobin
What do type 1 muscle fibers use for energy
Fatty acid - oxidative phosphorylation
Which muscle fiber type is used for rapid discontinuous contractions
Type 2
Type 2 has ______ myoglobin than type 1
Less
What are the three subtypes of type 2 muscle fiber
IIA
IIB
IIC
Which subtype has the fastest action and uses glycolysis for energy
IIB
Sarcoplasmic reticulum store
Calcium
Sarcoplasmic reticulum is a network of _______
SER
What is the T-tubule?
Projection of sarcolemma that forms a complex of tubules at the A-I junction
What makes up a triad?
1 T-tubule and 2 terminal cistern
What triggers calcium to be released?
When the action potential contacts a terminal cistern
What do skeletal muscles use as their neurotransmitter?
Ach
What determines if a muscle can contract?
The number of receptors
What happens if enough Acetyl-CoA is bound to peripheral protein on the muscle?
The muscle depolarizes and action potential is sent into the muscle
What does type 2 skeletal muscle use for energy?
Glycolysis
