Human Anatomy & Physiology - The Muscular System & Nervous Tissue

Flashcards covering key concepts related to the muscular system and nervous tissue in human anatomy and physiology.

Endomysium

A thin connective tissue surrounding individual muscle fibers.

Fascicle

A bundle of muscle fibers wrapped in perimysium.

Perimysium

The connective tissue that surrounds fascicles.

Epimysium

The outer layer of connective tissue encasing the entire muscle.

Skeletal Muscle Fiber

The basic unit of a skeletal muscle, distinguished by its structure and function.

Agonist

A muscle that is primarily responsible for a specific movement.

Antagonist

A muscle that opposes the action of an agonist.

Synergist

A muscle that assists the agonist in performing its action.

Fixator

A muscle that stabilizes the origin of the agonist.

Lever System

A mechanical system of bones and muscles that allows movement, consisting of a fulcrum, effort, and load.

Sarcolemma

The cell membrane of a muscle fiber.

Myofibril

The contractile filament within muscle fibers made up of sarcomeres.

Sliding-Filament Mechanism

The process in which muscle fibers contract by the overlapping of thick and thin filaments.

Motor Unit

A motor neuron and all the muscle fibers it innervates.

Neuromuscular Junction

The synapse between a motor neuron and a muscle fiber, facilitating muscle contraction.

Action Potential

A temporary change in electrical potential across a cell membrane that initiates muscle contraction.

Resting Potential

The electrical charge difference across the membrane of a neuron when it is not actively transmitting a nerve impulse.

Repolarization

The process of restoring the resting potential in a neuron after depolarization.

Neurotransmitter

Chemical messengers that transmit signals across a chemical synapse from one neuron to another neuron or muscle cell.