AY Honors/Ecology - Advanced/Answer Key
1. Have the Ecology Honor.
2. State the first and second laws of thermodynamics and explain how they are important to ecology.
First Law
- ”In any process, the total energy of the universe remains constant.”
More simply, the First Law states that energy cannot be created or destroyed; rather, the amount of energy lost in a steady state process cannot be greater than the amount of energy gained.
This is the statement of conservation of energy for a thermodynamic system. It refers to the two ways that a closed system transfers energy to and from its surroundings - by the process of heating (or cooling) and the process of mechanical work. The rate of gain or loss in the stored energy of a system is determined by the rates of these two processes. In open systems, the flow of matter is another energy transfer mechanism, and extra terms must be included in the expression of the first law.
In an ecological sense, the first law shows that a creature's energy must come from somewhere, and it must go somewhere as well. Primary producers transfer energy from the sun to primary consumers to secondary consumers at the top of the food chain. All along the way, some of the energy is dissipated in the form of heat.
Second Law
- “The entropy of an isolated system not in equilibrium will tend to increase over time, approaching a maximum value at equilibrium.”
In a simple manner, the second law states that "energy systems have a tendency to increase their entropy" (heat transformation content) rather than decrease it.
A way of looking at the second law for non-scientists is to look at entropy as a measure of chaos. So, for example, a broken cup has less order and more chaos than an intact one. Likewise, solid crystals, the most organized form of matter, have very low entropy values; and gases, which are highly disorganized, have high entropy values.
3. Explain the three basic trophic (feeding) levels and give a good example of a plant or animal for each.
4. Explain or diagram the three types of ecological pyramids in the food web. Give an example of each layer of the pyramid.
5. Define the biogeochemical cycle, and explain or diagram all the basic components the cycle passes through.
6. Diagram or explain the basic steps in the flow of energy through the biotic environment (element) of an ecosystem. Begin with the sun.
7. Explain Liebig's Law of The Minimum and Shelford's Law of Tolerance, and state how these laws tell us how and why certain plants and animals become endangered or are eliminated when their habitat or community gets disturbed OR out of balance.
8. Choose a biological community in your area, such as a forest or woods; a swamp, lake or pond; pasture or meadow grassland; or a canyon or creek woods, etc., that is disturbed or ecologically out of balance in some way. Make a description of it, including how and to what extent it is disturbed. Then make recommendations as to how the community could be improved and, where possible, follow through and help to improve it in some way.
9. Spend a minimum of 20 hours doing active, productive work on an ecology project in your area. This may be done individually or as a group. Describe the project in general, but report specifically on your part in it.
10. Define the following terms:
a. Community
b. Raw materials
c. Photosynthesis
d. Chemosynthesis
e. Autotrophy
f. Heterotrophy
g. Ecological balance
h. Saprobe
i. Decomposer
j. Producer
k. Consumer
l. Limited factor
11. Find a Spirit of Prophecy quotation and a Bible text pertinent to ecology and explain their relevance and application to our day.
Adventist Youth Honors Answer Book/Ecology quotations
