Which statement best describes how scientists formed cell theory? a. schwann observed that plants are made of cells and shared his theory at conferences. b. pasteur observed that cork was made of cells and published his findings widely. c. remak wrote cell theory after realizing that cells cannot come from non-living matter. d. multiple scientists and observations contributed to the formation of cell theory.

Female luna moths (actias luna) attract males by emitting chemical signals that spread through the air. a male hundreds of meters away can detect these molecules and fly toward their source. the sensory organs responsible for this behavior are the comblike antennae visible in the photograph shown here. each filament of an antenna is equipped with thousands of receptor cells that detect the sex attractant. based on what you learned in this chapter, propose a hypothesis to account for the ability of the male moth to detect a specific molecule in the presence of many other molecules in the air. what predictions does your hypothesis make? design an experiment to test one of these predictions.