stabilizes and supports components of skeletal muscle Surrounds muscle at each organization level.
How many muscles does the human body contain?
600 (40-50% body weight)
Basic skeletal muscle unit. Capable of force production and shortening. Arrangement of protein filaments and gives straight appearance.
can bind calcium
ATP production through aerobic metabolism
As Sarco Shortens
actin filaments slide over myosin. Z-lines approach end of myosin filaments
As Sarco relaxes
It returns to original length Less overlap between actin and myosin
The sliding filament theory
• Formation of cross bridges between actin and myosin filaments. • Reduction in distance between z-lines or sarcomere "power stroke" • ATP is required for muscle contraction o Myosin ATPase breaks down ATP as fiber
o oxidative capacity o type of ATPase
o maximal for production o Speed of contraction o muscle fiber efficiency