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.
Writing the Opening. 1  1. Address your letter to a specific person, if possible. Introductory letters should be addressed to the person who will be reading it, whenever possible. 2  2. State your purpose clearly. As early as possible in a letter of introduction, you need to express your reason for writing.