Arrange the statements below to describe how a lake might become a forest in a period of 100 years. Fill in 1 to 5, 1 being the first to occur. (It's not 5, 4, 3, 2, 1) __ These processes continue until the lake is replaced by a forest.
__ Seeds from trees are dropped on the shore and trees begin to grow.
__ Pine needles, leaves, and branches from shoreline trees drop into the water thereby reducing the lake and expanding the shore.
__ Lichens and bacteria break down rocks near the shore into soil.
__ Lack of rain results in reduced water levels and an expanded shore.

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.