TeXes Science Practice Test

What term describes a detectable change in an organism's environment?

1. Response

2. Stimulus

3. Adaptation

4. Evolution

The correct answer is: Stimulus

The term "stimulus" refers to a detectable change in an organism's environment. Stimuli can be anything from changes in temperature, light, sound, or pressure that trigger a response from an organism. This response can be physiological, behavioral, or both, depending on the nature of the stimulus. For example, when a bright light is shone into a room, a person may squint; in this case, the light serves as the stimulus prompting the response. Understanding stimuli's role is fundamental in biology, particularly in the context of how organisms interact with their environment, respond to changes, and maintain homeostasis. The other terms listed, while related to biological processes, do not specifically capture the concept of a change that triggers an organism's response in the same way.