4-1 Reading Guide                                                                         Name:  ________________________________

1.  _____________________ is the day to day condition of Earth’s atmosphere at a particular time and place. 
2. Climate refers to the average ____________________    __________________     _____________
   conditions of  temperature and precipitation in a particular region.
3. _______________________,  _____________________,  ___________________ and a few other atmospheric   gases trap heat energy and maintain Earth’s temperature range.
4. If these gases were not present the Earth would be _________° cooler.
5. Because Earth is a sphere that is tilted on its axis, solar radiation strikes different parts of the Earth’s surface at an angle that  __________________________________________________________________________.
6. Earth’s three main climate zones are ____________________, ___________________, _____________________.
7. The upward movement of ____________________air and the downward movement of _______________ air create air currents, or winds.
8. ___________________________ patterns of heating and cooling occur in the Earth’s oceans.
9. _________________________ and other ______________________ can also affect winds and ocean currents.

4-2  What shapes an Ecosystem?                          

1.  Define biotic factors: __________________________________________________________________
   Define abiotic factors: __________________________________________________________________
2. The area where an organism lives is called its _________________________________.
3. If an organism’s habitat is its _____________________________, it niche is its _________________________.
4. No two species can ______________________ the same niche in the same __________________________.
5. What is competition? ______________________________________________________________________
6. The competitive exclusion principle states that _________________________________________________
   _______________________________________________________________________________________
7. Give an example of a predator and its prey.  ____________________________________________________
8. What are the three types of symbiosis?  _______________, _______________, and _______________.
9. In figure 4-6, what would happen to the aphids if the ant died? _____________________________________
10. _______________ are constantly changing in response to natural and ___________________ disturbances.
11. Compare and contrast primary and secondary succession. ________________________________________
    ___________________________________________________________________________________ 
12.  What are pioneer species?  ___________________________________________________________________
    And give an example.  _______________________________________________________________________
13. Figure 4-9 illustrates the stages in a ___________________   --   _______________________ community.
14. What are the first organisms to be attracted to the whale carcass? __________________________________
15. What organisms decompose whale oil? ___________________________________