The tendency to respond to a stimulus that is similar, but not identical, to the original conditioned stimulus is called A) stimulus generalization. B) spontaneous recovery. C) stimulus adaptation. D) extinction.

What did hunter gathers do to alter the environment?

Which of the following statements about archaea and bacteria is true? a. neither is single-celled. b. they both have nuclear membranes. c. neither reproduces by binary fission. d. they both lack a nuclear membrane.

Why are scientists concerned about the depletion of the ozone levels in the stratosphere?