The last common ancestor of all animals was probably a

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.

Which areas of earth receive the most precipitation on average? a. tropics b. temperate zones c. regions near 30? n and s latitudes d. polar zones 1

Which of the following statements about brain development and early childhood is true? the brain of a 5 year old is 60 percent the size of an adult brain the overall size of the brain does not increase dramatically from ages 3-15 by the time a child is 3 years of age, the brain is 25 percent of it's adult size the development that occurs inside the brain ends at the onset of adolescence