The Muscular System: Microscopic Anatomy and Physiology of Skeletal Muscle

These flashcards cover key vocabulary terms and definitions related to the microscopic anatomy and physiology of skeletal muscle as discussed in the lecture.

Skeletal muscle

Voluntary, striated muscle tissue that is attached to bones.

Myofibril

The basic unit of muscle structure that actually contracts and has striations.

Sarcoplasm

Cytoplasm of a muscle cell.

Neuromuscular junction

The site where a motor neuron meets a muscle fiber to transmit signals for contraction.

Acetylcholine

A neurotransmitter that transmits impulses at the neuromuscular junction.

Motor unit

A motor neuron and all the muscle cells it innervates.

Striations

The alternating light and dark bands found in skeletal and cardiac muscle.

Myofilament

Filaments that make up myofibrils; includes thick (myosin) and thin (actin) filaments.

Sarcoplasmic reticulum

An organelle similar to smooth endoplasmic reticulum that stores calcium ions and helps transmit impulses.

T-tubules

Transverse tubules that help conduct electrical impulses into the muscle cell.

Acetylcholinesterase

An enzyme that breaks down acetylcholine, preventing continuous muscle stimulation.

Synapse

Junction between two neurons or between a neuron and a muscle or gland cell.