Compare and contrast nervous and hormonal mechanisms for control and coordination in animals.

What is the need for a system of control and coordination in an organism?

Compare and contrast biomass and hydroelectricity as sources of energy.

Compare and contrast fossil fuels and the sun as direct sources of energy.

How does chemical coordination take place in animals?

Compare and contrast the arrangement of elements in mendeleev's Periodic Table and Modern Periodic Table.

What is a semiconductor? Describe the two main types of semiconductors and contrast their conduction mechanism.