Stimulus

Real World Example

Imagine you're peacefully enjoying your morning coffee when the shrill sound of a fire alarm suddenly rings out. Just like the fire alarm disrupts your tranquility and causes you to jump up, looking for the source of the disturbance, a stimulus in science is anything that causes an organism to react. In this analogy, the fire alarm acts as the stimulus, your sudden alertness and actions represent the organism's response, demonstrating how stimuli trigger reactions in both everyday life and biological systems.