Provide "acknowledged body of knowledge" related to the concept. Emphasize the most significant aspects of the concept in an organized, organic manner. Present information sequentially so students see continuity. Draw attention to important, discrete details; don't swamp students with myriad facts.

Instruction on photosynthesis and respiration and how these two interdependent processes form the basis of the "Circle of Life."

Objective: Instruction on photosynthesis and respiration and how these two interdependent processes form the basis of the "Circle of Life."

Activity:
1) discuss what is meant by the "Circle of Life”
2) Before beginning formal instruction, students engage in an inquiry into the relationship between a plant and animal. The students are given 7 hypotheses concerning whether plant and animals take in or give off carbon dioxide in the light and in the dark. Students then make predictions, design experiments and carry them out to test the hypotheses. The animals used are aquatic snails that students collect locally and the plant is elodea that I pick up at the pet store. A prelab is conducted in which students blow into beakers of water and Bromothymol blue (BTB) with a straw, turning the blue solution to green and then yellow. From this the students infer that BTB can be used to indicate the presence of absence of CO2. Most students predict that the plant in the dark will still take in CO2 and are surprised when it actually gives off CO2. (Lab is from Biology: As Scientific Inquiry) This primes students for a discussion and lecture on photosynthesis and respiration.
3) PowerPoint Lecture on Photosynthesis and Respiration, connecting to how these two interdependent processes make up the basis of the "circle of life."
4) Photosynthesis and Respiration Video
5) Laser Disk visuals and video clips
6) Introduce ecosystems and related terminology, focusing on the loss of energy as it flows from the sun to each of the trophic levels.