Please enable JavaScript.
Coggle requires JavaScript to display documents.
Alicia Resmer Period 5 Muscular - Coggle Diagram
Alicia Resmer Period 5 Muscular
Disorders associated w Muscular System
Muscular Dystrophy- genetic disease that causes progressive weakness and degeneration to skeletal muscle
Fibromyalgia- Muscle pain caused physical trauma
Myasthenia Gravis- Blocked neurotransmitter autoimmune disease
Cerebral Palsy- Spastic paralysis caused by muscle weakness (premature birth, bleeding in brain, head injury)
Myositis- Muscle Inflammation
Main Functions
Protection
Heat
Support
Blood circulation
Movement
3 main muscles and functions
Skeletal muscle – the specialised tissue that is attached to bones and allows movement.
Smooth muscle – expanding and contracting passage that allows food and fluid to move through body
Cardiac muscle – The heart contracts and relaxes without our conscious awareness.
Muscle Coverings
Epimysium: The outermost layer of tissue surrounding the entire muscle.
Perimysium: The middle layer surrounding bundles of muscle fibers.
Endomysium: The innermost layer surrounding individual muscle fibers.
Sliding Filament Theory
Sliding Filament Theory suggests that muscle contraction is caused by thin filaments sliding over thick filaments causing muscle contraction
The sliding filament contraction occurs in the sarcomere region.
The myosin filaments ratchet over actin filaments contracting the sarcomere.
The I and H bands within the sarcomere compress and expand to facilitate the movement.
The myofilaments do not expand and contract on their own.
Sarcomere
basic contractile unit of muscle fiber
A band
Region of striated muscle that contains thick filament
Z Line
defines boundary of sarcomere
I Band
Light band that contains thin filament and lies between two thick filaments
Thick and Thin Filaments
Thick contains Myosin and Thin contains actin
H Zone
Contains Myomesin, middle of sarcomere
Myosin and Actin
responsible for cell movements
tropomyosin
Regulates contraction
Neuromuscular Juntion
1, AP travels from axon to axon terminal
Voltage-Gated calcium channels open and the calcium enters the axon terminal
3.Calcium causes vesicles to release ACH into the synaptic cleft
4, ACH diffuses across the synaptic cleft and binds to the receptors
The binding of the ACH opens the ion channels and sodium rushes into the muscle
If the muscle reaches the threshold (-55mv) at the motor end plate then AP will occur on the muscle .
ACH is broken down by Acetylcholineesterase