A&P Chapter 4 Flashcards
Thread-like structures that extend from one end of the muscle fiber to the other
Myofibrils
The process by which ions are moved across the cell wall to return to a polarized state
Repolarization
The muscle in a group of muscles that has the major role in movement
Prime Mover
The longest muscle in the human body, it is located in the anterior compartment of the thigh and flexes both the hip and knee when it contracts
Sartorius Muscle
The connective tissue sheath that surrounds a muscle and forms sheaths for the bundles of muscle fibers
Perimysium
A bundle of skeletal muscle cells bound together by connective tissue and forming one of the constituent elements of a muscle
Muscle Fasciculus
A condition caused by damage, either through trauma or infection, to the facial nerve, resulting in an inability to move the facial muscles on the affected side
Bell Palsy
A prime mover; a muscle that contracts to provide most of a desired movement
Agonist
An organic compound in muscle tissue that can store and provide energy for muscle contraction
Creatine Phosphate
An iron-containing red pigment, similar to hemoglobin, that is found in muscle fibers
Myoglobin
The repeating patterns of striation units that appear a long each skeletal muscle fiber
Sarcomeres
The bones and voluntary muscles of the body
Musculoskeletal System
Deep muscles of the medial compartment that adduct, flex, and internally rotate the thigh
Pectineus Muscles
A chemical neurotransmitter that serves as a mediator in both the sympathetic and parasympathetic nervous system
Acetylcholine
The thin transparent sheath surrounding a striated muscle fiber
Sarcolemma
An electrochemical event associated with cell membrane depolarization that occurs when a cell or tissue has been activated by a stimulus
Action Potentials
A method of action of muscle contraction involving how sarcomeres shorten, with thick and thin filaments sliding past each other toward the center of the sarcomere from both ends
Sliding Filament Model
The linear muscle of the midline of the abdomen
Rectus Abdominis
An enzyme that causes muscle relaxation by helping to break down acetylcholine
Acetylcholinesterase
Movement of the eyes in various directions
Extraocular Movements
Areas of alternating, colored bands of skeletal muscle fiber
Striations
Muscles of respiration that elevate the first two ribs during inspiration
Scalene Muscles
The component that makes up most of the thick protein filaments of the myofibrils
Myosin
A moveable part of the body to which a skeletal muscle is fastened at a moveable joint
Insertion
One of the two types of smooth muscle, it is formed into sheets of muscle (as in the walls of blood vessels), small bundles of muscles (as in the iris of the eye), or single cells (as in the capsule of the spleen)
Multiunit Smooth Muscle
The short muscle that adducts the thigh
Adductor Brevis
Sheets of muscle found in the digestive, reproductive, and urinary tracts
Visceral Smooth Muscle
A test used to evaluate the integrity of the Achilles tendon for possible rupture
Thompson Test
The junction between a motor neuron and a muscle fiber; one type of a synapse
Neuromuscular Junction
The strong tendon that joins the muscles in the posterior leg to the calcaneus
Achilles Tendon