• Cell — the basic unit of life
• Tissue — groups of similar cells performing a shared function
• Organ — structures composed of multiple tissue types
• Neuron — the cell that generates and transmits electrical signals
• Synapse — the junction where neurons communicate
• Receptor — a protein that detects a specific signal and initiates a response
• Action Potential — the electrical impulse that travels along a neuron
• Inflammation — the body’s response to injury or infection
• Homeostasis — the maintenance of stable internal conditions