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Muscular System (Bio101)
End of an axon that contains vesicles filled with the neurotransmitter acetylcholine
A functional level of muscle tissue made up of actin and myosin filaments. These are responsible for muscle contractions
Basic functional unit of a muscle cell.
A partial but sustained muscle contraction. Common in muscles of the back
When a muscle fiber descides to contract, it will contract completely
Contraction of muscles without changing the length of the muscle. Example: standing at attention, pushing a wall
An energy supply for the synthesis of ATP molecules.
Protein molecule that stores oxygen
Muscle growth from training or usage
Lack of muscle usage leading to decrease size, tone, and power
Contraction of muscles that changes the length of the muscle. Examples: lifting objects, running
Energy source for muscle contractions. Without it muscles may cramp and not contract
Voluntary, striated muscle found through out the entire body
Involuntary, striated muscle found only in the heart. Contains intercalated disks
Involuntary, non-striated muscle found in vessels and organs.
Less moveable end of muscle attachment. Fixed end
Moveable end of muscle attachment.
The movement made based on the muscle. Example: flexion
AKA "six-pack" inserts on the superior surface of the pubis and around the symphysis
Muscle that when contracted causes the arm to flex
Muscle that when contracted causes extension of the arm. Extends arm during push ups