Chapter 6; Muscles Flashcards
Acetylcholine
A chemical transmitter substance released by certain nerve endings
Abduction
To move away from the midline of the body
Actin
A contractile protein of a muscle
Action potential
An electrical current occurring when a stimulus of sufficient intensity is applied to a neuron or muscle cell, allowing sodium ions to move into the cell and reverse the polarity
Adduction
To move toward the midline of the body
Aerobic respiration
Using oxygen to breath/function
Anaerobic respiration
Not using oxygen to breath/function
Antagonists
Muscles that act in opposition to an agonist or prime mover
Aponeurosis
Fibrous or membranous sheet connecting a muscle and the part it moves
Creatine phosphate
a phosphorylated creatine molecule that serves as a rapidly mobilizable reserve of high-energy phosphates in skeletal muscle and the brain
Dorisflexion
Flexing of the back
Extension
To elongate or straighten out
Fixators
Muscles acting to immobilize a joint or a bone; fixes the origin of a muscle so that muscle action can be exerted at the insertion
Flexion
Bending; the movement that decreases the angle between bones
Insertion
The movable attachment of a muscle as opposes to its origin
Lactic acid
The product of anaerobic metabolism; especially in muscles
Motor unit
A motor neuron and all the muscle cells it supplies
Myofibrils
Contractile organelles found in the cytoplasm of muscle cells
Myosin
One of the principal contractile proteins found in muscle
Neuromuscular junction
The region where a motor neuron comes into close contact with a skeletal muscle cell
Neurotransmitter
Chemical released by neurons that may, upon binding to receptors of neurons or effector cells, stimulate or inhibit them
Origin
Attachment of a muscle that remains relatively fixed during muscular contraction
Oxygen debt
The volume of oxygen required after exercise to oxidize the lactic acid formed during exercise
Plantar flexion
Flexion of foot
