A student performed an activity with soil and water. The table below shows the kind of soil that was added to each of two cans. After the soil was added, holes were made in the bottom of each can. Then a total of 200 milliliters of water was added to each can. The water that dripped from each can was collected for one minute. Which of the following is an observation in this experiment?* Soil Experiment Volume of Water Type of Soil Collected in One Minute (mL) Clay 55 Sand 110 h Sunlight heats water in clay faster than water in sand. Plants grow better in clay than in sand. Water flows through sand faster than through clay. Insects are more active in sand than in clay.

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.