Chapter 4: The Musculoskeletal System Flashcards
A chemical neurotransmitter that serves as a mediator in both the sympathetic and parasympathetic nervous system
Acetylcholine
The enzyme that causes muscle relaxation by helping to break down acetylcholine
Acetylcholinesterase
The strong tendon that joins the muscles in the posterior leg to the calcaneus
Achilles Tendon
The component that makes up most of the thin protein filaments of the myofibrils
Actin
Changes in electrical potential that occur when a cell or tissue has been activated by a stimulus
Action Potentials
The short muscle that adducts the thigh
Adductor Brevis
The long muscle that adducts the hip
Adductor Longus
A prime mover; a muscle that contracts to provide most of a desired movement
Agonist
The area within the pelvis that contains the anus
Anal Triangle
Muscles working in opposition to each other
Antagonists
Broad sheets of fibers that may attach to bones or to the coverings of other muscles
Aponeuroses
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
Located in the posterior compartment of the leg; flexes and laterally rotates the knee and extends the hip
Biceps Femoris
An intracellular protein to which calcium binds, resulting in muscle contraction
Calmodulin
Muscle that is found only in the heart, providing the contractions needed to propel the blood through the circulatory system
Cardiac Muscle
Accumulation of blood or fluid in a fascial compartment, typically following trauma, resulting in compression of blood vessels and tissue damage secondary to ischemia and, if not recognized and promptly treated, death of muscle and loss of the limb
Compartment Syndrome
Anatomic spaces within the body that are enclosed by fascia
Compartments
An organic compound in muscle tissue that can store and provide energy for muscle contraction
Creatine Phosphate
The rapid movement of electrolytes across a cell membrane that changes the cell’s overall charge. This rapid shifting of electrolytes and cellular charges is the main catalyst for muscle contractions and neural transmissions
Depolarization
A muscular dome that forms the undersurface of the thorax, separating the chest from the abdominal cavity. Contraction of this muscle (and the chest wall muscles) brings air into the lungs. Relaxation allows air to be expelled form the lungs
Diaphragm
The delicate connective tissue surrounding individual muscular fibers
Endomysium
A layer of connective tissue that closely surrounds skeletal muscles
Epimysium
Groups of muscles that cause extension
Extensor Muscles
Fluid outside of the cells, in which most of the body’s supply of sodium is contained; accounts for 15% of body weight
Extracellular Fluid
Movement of the eyes in various directions
Extraocular Movements
A layer of fiberous connective tissue outside the epimysium that seperates individual muscles and individual muscle groups
Facia
Groups of muscles that cause flexion when contracted
Flexor Muscles
Conduction areas between cells (eg, in visceral smooth muscle) that interconnect individual muscle cells
Gap Junctions
An iron-containing protein within red blood cells that has the ability to bind to oxygen
Hemoglobin
A movable part of the body to which a skeletal muscle is fastened at a movable joint
Insertion
Branching fibers in cardiac muscle that allow action potentials to pass from cell to cell
Intercalated Disks
The ability of a muscle to generate its own electrical activity
Intrinsic Automaticity