Muscle and Nervous System Review

These flashcards cover fundamental vocabulary and concepts related to muscle and nervous systems, assisting in exam preparation.

Muscle Fiber

The basic unit of skeletal muscle, composed of long, cylindrical structures called myofibrils.

Myofibrils

Long, cylindrical structures within muscle fibers that assist in muscle contraction.

Actin

A protein forming the thin filaments of muscle fibers with a helical shape; contains myosin binding sites.

Myosin

A thick filament protein with a globular head and an elongated tail that interacts with actin during muscle contraction.

Sarcolemma

The plasma membrane enclosing a muscle fiber.

Sarcoplasm

The cytoplasm of a muscle fiber that contains organelles and contractile proteins.

Sarcoplasmic Reticulum

An internal membrane complex in muscle fibers that stores calcium ions.

Transverse Tubules

Deep invaginations of the sarcolemma that aid in transmitting electrical signals to the sarcoplasmic reticulum.

Neuromuscular Junction

The synapse between a motor neuron and a skeletal muscle fiber, critical for muscle contraction.

Acetylcholine (ACh)

A neurotransmitter released at the neuromuscular junction that binds to receptors on muscle fibers.

Calcium (Ca2+)

An ion that binds to troponin during muscle contraction, leading to exposure of myosin binding sites on actin.

Crossbridge Cycling

The process through which myosin heads pull actin filaments during muscle contraction.

Creatine Phosphate

A high-energy compound in muscle cells that provides quick regeneration of ATP.

Glycolysis

The anaerobic process of breaking down glucose to form ATP in muscle cells.

Aerobic Cellular Respiration

The process of producing ATP in the presence of oxygen, yielding more energy than glycolysis.

Skeletal Muscle

Striated muscle type composed of long fibers, responsible for voluntary movements and body posture.

Smooth Muscle

Involuntary, non-striated muscle found in internal organs, responsible for involuntary movements.

Cardiac Muscle

Striated, involuntary muscle that makes up the heart and is controlled by the autonomic nervous system.

Agonist

A muscle that contracts to produce a specific movement.

Antagonist

A muscle that opposes the action of an agonist, allowing for smooth movement.

Reflex Arc

The neural pathway involved in reflex actions, typically involving sensory and motor neurons.

Saltatory Conduction

A rapid form of action potential propagation in myelinated axons, where the impulse jumps between nodes of Ranvier.

Blood-Brain Barrier (BBB)

A selective barrier that regulates passage of substances from the bloodstream into the brain.

Cerebrospinal Fluid (CSF)

A clear fluid surrounding the brain and spinal cord, providing buoyancy and protection.

Limbic System

A complex set of structures in the brain involved in emotion, memory, and arousal.

Thalamus

A brain structure that serves as a relay station for sensory information.

Hypothalamus

The brain region controlling autonomic functions, endocrine activities, and coordinating the nervous system.

Diencephalon

A brain area comprising the thalamus and hypothalamus, involved in sensory and motor signal relay.

Action Potential

An electrical signal that travels along axons, triggering neurotransmitter release at synaptic junctions.