Food for thought worksheet answers

Food for thought….. Trophic levels Plants make food during photosynthesis; they are called primary producers or autotrophs. Animals eat the food. They are known as consumers or heterotrophs. 1. What does the suffix “troph” mean? 2. What do you think a trophic level is? 3. How about food chains, food webs? Compare and contrast those terms you learned in biology. 4. Quickly sketch a food chain using organisms that might be found on our school grounds. a. What do you have to do to turn it into a food web? Do so. 5. Look at the following diagrams called Energy Pyramids. a. What do they all have in common? b. How are they different from one another? 6. Why do you think there are more organisms at the base and less organisms as you travel up the pyramid? a. Any idea what an energy pyramid shows? 7. Two of the pyramids have numbers. Do you see a pattern in the numbers? a. What might the numbers mean? Read the following description from Earth Force Energy pyramids, otherwise known as trophic level diagrams, are used to represent the flow of energy through an ecosytem. An organism’s trophic level indicates the organism’s position in the sequence of energy transfers. There are two apparent trends represented in an energy pyramid. First, there are enormous numbers and masses of individual animals or plants at the bottom and the numbers decrease as you reach the top. Secondly, the sizes and energy needs of the individual organisms generally increase as you reach higher levels. The bottom, or base, of an energy pyramid is a position always held by the producers and represents (by far) the largest percentage of biomass for the food web. The need for such a large biomass of producers is to support the energy needs for all the organisms at higher trophic levels. In the illustration above, the osprey is positioned at the highest trophic level. Therefore, for the energy transformations represented by the pyramid, the osprey is the organism with the greatest energy needs and relies on all of the transactions from producers to consumers to have enough energy left over to fill its own energy needs. It should be acknowledged that ecosystems are very complex and any food chain, food web or energy pyramid simply illustrates the general idea. It would be practically impossible to illustrate all the possible ways that animals interact and all the possible ways that energy moves throughout an ecosystem. Next, now that you’ve thought about food chains, energy pyramids and so on, let’s do some problem solving. As you do these, think about the benefits and drawbacks of eating at lower trophic levels. First, for some background, read about soybeans from the Small Bean, Big Dreams “Small bean, big dreams” is a fitting motto for the versatile soybean plant. Known as the “Cadillac” of protein sources, soybeans nourish the people and animals of the world. Soybeans also help us reduce reliance on petroleum through hundreds of renewable product innovations that enhance our everyday lives. All this from a bean so small that it takes around 150,000 soybeans to fill one bushel. Good things do come in small packages! Soybeans have a rich history from their creation in China 5,000 years ago.