Which term is defined as a process that explains how something happens, often involving steps or causes?

• A. Fossil
• B. Adaptation
• C. Competition
• D. Mechanism

Answer: (D)

Mechanism is the term that describes a process explaining how something happens, often laying out the step-by-step sequence or the causal factors that lead to an outcome. It focuses on the “how” behind a phenomenon, not just what is observed. For example, the mechanism of muscle contraction details how calcium triggers binding site exposure and how ATP-powered cross-bridge cycling drives movement, showing the chain of events that produce the result. Fossil refers to preserved remains, adaptation is a trait that improves fitness, and competition is the interaction between organisms for resources; none of these center on the explanatory steps that connect causes to effects like a mechanism does.