Lab 19

sarcolemma

cell membrane of a muscle fiber

myosin

protein found within thick filament

fascicle

small bundle of muscle fibers within a muscle

sarcoplasmic reticulum

cellular organelle in muscle fiber corresponding to the endoplasmic reticulum

fascia

connective tissue located between adjacent muscles

biceps brachii

contracts when forearm is flexed at the elbow

synergists

assisting muscles of an agonist

origin

attached to a fixed location

tendon

cordlike part that attaches a muscle to a bone

epimysium

layer of connective tissue that surrounds a skeletal muscle

sarcomere

unit of alternating light and dark striations between Z lines

insertion

usually attached to a more movable location

transverse (T) tubule

membranous channel extending inward from muscle fiber membrane

triceps brachii

act as an agonist when forearm is extended at the elbow

prime mover

an agonist that provides the most force of a specific action is sometimes referred to as

sarcoplasm

cytoplasm of a muscle fiber

perimysium

layer of connective tissue that separates a muscle into small bundles of fascicles

endomysium

layer of connective tissue that surrounds an individual muscle fiber

agonist

muscle responsible for an action

antagonist

muscle that resists the actions of agonist and cause movement in the opposite direction