Just like a food chain, energy enters the food web at the trophic level of the producers, which can also be called autotrophs. In the desert, autotrophs are often some type of cactus, grass, or shrub.
The main purpose of the INTRODUCTION is to give a description of the problem that will be addressed. In this section the researcher might discuss the nature of the research, the purpose of the research, the significance of the research problem, and the research question(s) to be addressed. Three essential parts of a good introduction are: RATIONALE.
Typically, the introduction is short (less than 10% of the word length) and you should: 1  Name the work being reviewed as well as the date it was created and the name of the author/creator. 2  Describe the main argument or purpose of the work. 3  Explain the context in which the work was created.