Final answer:
Structuralism examines the structure of mental processes, while functionalism studies the function of mental activities in adaptation to the environment.
Step-by-step explanation:
The key difference between structuralism and functionalism in psychology lies in their focus and approach to studying the mind. Structuralism, pioneered by Wilhelm Wundt, focuses on the contents and structure of mental processes, using methods like introspection to analyze the conscious experience into its basic elements. On the other hand, functionalism, influenced by thinkers like William James and John Dewey, concentrates on the function of mental processes and behavior in adapting to the environment, emphasizing the role of the mind as a whole in helping an organism survive and thrive.