Muscular System Flashcards
Muscular System
Integrated system that vitally controls involuntary and voluntary movement.
Types of Muscular Tissue
Three Types of muscular tissue: Skeletal, Cardiac, and Smooth.
Skeletal Muscle
Often attaches to bone and is involved in the movement of bones. Skeletal muscle is striated and very strong. It is the only voluntary muscle in the body.
Cardiac Muscle
Found in the heart and is also striated. Not controlled consciously, making it an involuntary muscle.
Smooth Muscle
Can be found in the walls of hollow organs( stomach, intestines, walls of blood vessels, eyes, reproductive tracts and skin. Weakest of all muscle tissues. Considered involuntary muscle because it is controlled unconscious part of brain.
Structure and Function of Muscles
Skeletal muscles are attached to bones by a tendon Tendons are bands of connective tissue that have strong collagen fibers. Firmly attach muscles to bone. Muscles move by contracting and shortening pulls tendons moving bone closer to another stationary bone. Named by location, shape, and size. Have long myrofibrils made of sarcomere units of proteins called actin( thin filaments) and myosin (thick filaments).
Nerves Control Muscles in the Nervous System
Each muscle fiber is connected to a nerve fiber. For entire muscle to move need nerves and fibers and ATP to power contraction and relaxation. When muscle is relaxed myosin and actin are NOT attached. When they contract filaments bind and are pulled together.
Brain sending a message to part of the body
Nervous system sends a signal to a muscle. Actin and Myosin slide past each other, creating a contraction or relaxation of the muscle.
Muscles respond to nerve impulses
Receptors in muscles allow them to receive a signal and respond to the appropriate magnitude and movement. Signal and response can be distributed by disorders ranging from muscle strain and muscular dystrophy.
Tissue
A group of cells with similar structure that function together as a unit, but at a lower level than organs.
Bone
Hard calcified material that makes up the skeleton.
Skin
The thin layer of tissue that covers the body.
Skeletal muscles
Muscles that attach to bones and are connected to and communicate with the central nervous system.
Tendons
Tough connective tissue that attaches muscle to bone
Collagen
The primary structural protein of connective tissue.
