Structures of the skeletal system Flashcards
What do muscles organs mainly consist of?
Striated muscle fibers and connective tissue
What does connective tissue form around the muscle fibers
It forms wrappers around the muscle fibers, around fascicles, and the entire muscle
What are fascicles
Groups of muscle fibers
Most skeletal muscles extend from one bone across a joint to another bone
Most skeletal muscles extend from one bone across a joint to another bone
what is an origin?
The origin is the fixed point that doesn’t move during contraction
What is Insertion
If the place is on the bone that moves during the action
What is a body
The main part of the muscle
What are tendons
Strong cords or sheets of connective tissue that extend from the muscle organ
What is tendon sheaths/synovial lining
a thin layer of tissue surrounds each tendon in the body and is lubricated by synovial fluid
What are the bursae
a closed, fluid-filled sac that works as a cushion and gliding surface to reduce friction between tissues of the body.
What are muscle fibers
Contractile cells, ex. connective tissue holds muscle fibers in parallel groupings
What are thick and thin myofilaments
The thick filaments are composed of myosin, and the thin filaments are mainly actin, along with two other muscle proteins, tropomyosin, and troponin. Muscular contraction is caused by the interaction between actin and myosin as they temporarily bind to each other and are released.
sarcomeres
are made up of regularly arranged contractile proteins (actin, myosin) that are responsible for skeletal muscle contraction. has z-lines that separate each other. basically, what gives skeletal muscle fibers a striated appearance
What does contraction require
Requires calcium and energy-rich ATP molecules
