Muscle Contraction

skeletal muscle

Vertebrate ________: moves bones and the body, characterized by a hierarchy of smaller and smaller units.

muscle contraction

physical interaction of protein filaments required for muscle function

muscle activity

response to input from the nervous system

vertebrate skeletal muscle

moves bones and the body, characterized by a hierarchy of smaller and smaller units

thin filaments

consists of two strands of actin and two strands of a regulatory protein

thick filaments

staggered arrays of myosin molecules

actin

a protein that forms (together with myosin) the contractile filaments of muscle cells, and is also involved in motion in other types of cells

myosin

a fibrous protein that forms (together with actin) the contractile filaments of muscle cells and involved in motion in other types of cells

sarcomere

functional unit of a muscle

tropomyosin

a protein involved in muscle contraction related to myosin and occurs together with troponin in the thin filaments of muscle tissue

two basic mechanisms by which nervous system produces graded contractions

varying the number of fibers that contract, varying the rate at which fibers are stimulated