These muscle cells are composed of many fibrils and contract when stimulated
What are muscle fibers?
These are the elongated threads found in striated muscle cells.
What are myofibrils?
The action of bending a limb or joint.
What is Flexion?
The electrical charge inside or around a nerve cell
What is Polarization?
A neurotransmitter found in the central, sympathetic and parasympathetic nervous systems.
What is Acetylcholine?
Also known as the calf muscle:
What is the Gastrocnemius muscle?
A tough cord or band of dense white fibrous connective tissue that connects muscle to bone.
What are tendons?
This protein, along with thin filaments made up of actin, compose structures called sarcomeres, which are the basic units of muscle contraction.
What is myosin?
The action of straightening a limb or joint.
What is Extension?
When the membrane potential becomes less negative (more positive).
What is Depolarization?
Muscle contraction occurs when these filaments slide over one another in a series of repetitive events.
What is Myosin and Actin?
This muscle originates at the manubrium of the sternum and has an insertion at the mastoid process of the temporal bone of the skull.
What is the sternocleidomastoid muscle?
A connective tissue that wraps around organs, providing support and holding parts together.
What is fascia?
This protein, found in all eukaryotic cells, forms filaments that make up a main component of the cell's cytoskeleton.
What is Actin?
The movement of a limb or other part toward the midline of the body.
What is adduction?
Refers to the change in membrane potential that returns it to a negative value just after the depolarization phase of an action potential has changed the membrane potential to a positive value.
What is Repolarization?
In a relaxed muscle, these chemicals block the attachment site for the myosin crossbridge, thus preventing contraction.
What is Troponin and Tropomyosin?
This muscle connects the upper extremity to the vertebral column and allows for rotation of the trunk:
What is the Latissimus Dorsi?
Dense, fibrous membrane covering the surfaces of bones, consisting of an outer fibrous layer and an inner cellular layer
What is the periosteum?
This large protein functions as a molecular spring, which is responsible for the passive elasticity of muscle.
What is Titin?
The movement of a limb or other part away from the midline of the body.
What is Abduction?
A momentary change in electrical potential on the surface of a neuron or muscle cell (also known as nerve impulses).
What is Action Potential?
An enzyme that splits acetylcholine into acetic acid and choline. Called also acetylcholinesterase.
What is Cholinesterase?
A group of muscles located in the front of the thigh, containing four muscles:
What are the quadriceps?
The muscle site that does not move during contraction (anchor point).
What is origin?
This protein works with troponin, regulating the interaction of actin and myosin in muscular contraction.
What is Tropomyosin?
This term is used for the movement when we point our toes, or stand on our tip-toes.
What is Plantar Flexation?
Release the neurotransmitters of the presynaptic cell.
What are Axon Terminals?
The energy currency of life.
What is ATP?
A thick, fan-shaped muscle, situated at the chest (anterior) of the human body:
What is the Pectoralis major?
The point of attachment in a muscle where more movement occurs.
What is the insertion site?
A system of membrane-bound tubules that surrounds muscle fibrils, releasing calcium ions during contraction and absorbing them during relaxation.
What is a Sacroplasmic reticulum?
When rotating our forearms or feet, this term is used to describe our palms and soles facing forward of our body.
What is Supination?
Junctions between two nerve cells, consisting of a minute gap across which impulses pass by diffusion of a neurotransmitter.
What is a synapse?
A waste byproduct that is generated from muscle metabolism.
What is Creatinine?
This muscle is located on the outer aspect of the shoulder and is recognized by its triangular shape and common site for IM injections:
What is the Deltoid?