Which of the following behaviors allows a bird to maintain a constant body temperature in extremely hot weather?
a. spreading wings
c. flattening feathers
b. panting
d. all of the above
user: bird bones are adapted for flight because they
a. are dense
c. are hollow
b. contain bone marrow
d. are longer than the bones of most animals

What happens when water’s salinity increases? mass decreases. freezing point decreases. buoyancy of objects decreases. the amount of dissolved minerals decreases.

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.

Body temperature is tightly regulated in mammals for example when external temperatures drop too much the body of a mammal response by in order to it's core temperature.