You might wonder why plants would absorb C[O.sub.2] at night, fix it into malate, the then refix it into Calvin cycle sugars the next day.
Photosynthesis consists of two basic light reactions--photolysis and photophosphorylation--followed by the dark reactions of the Calvin cycle. Some plants are especially adapted to high temperature, high light intensity, and water stress because the enzyme system for capturing C[O.sub.2] is different, and the processes are separated in time or space.
Using one of the search engines on the Internet, such as Google, Yahoo!, Ask.com, or MSN Live Search, find more information by searching for these words or phrases: law of thermodynamics, energy conversion, anaerobic respiration, aerobic respiration, oxidation reduction, photosynthesis, pigments, light reactions, ATP, ADP, Calvin cycle, Krebs cycle, stomata, glycolysis, fermentation, glucose, protein, lipids, and amino acids.
Due to my general enthusiasm for biology, and all of the other biological plays and activities I employ in teaching, my students are used to and expect active participation in learning a complicated process such as the biochemistry of the Calvin cycle. Thus, I have not found student willingness to be a problem for any of the activities I employ in my class, including this activity.
As we perform this musical in the class, the characters sing the lyrics (in italics below) and the following events, written under Directions for each segment, are acted out: The Story of the Calvin Cycle Here's the story of RuBP Who was floating in the stroma on its own.
The regeneration steps demonstrate how the 3-carbon aldehydes join and split through a series of reactions that involve 3, 4, 5, 6, and 7-carbon compounds to yield the regenerated RuBPs in the final step of the Calvin cycle. We do not dwell on all of the enzymes involved in the regeneration steps.
Following the musical, there is a quick review of the major steps of the Calvin cycle and their relation to internal anatomy of the leaf and the photochemical reactions in the thylakoids.
What is accomplished in each of the three major steps in the Calvin cycle?
If we turn off the lights in the classroom to simulate night time, how will that affect the steps of the Calvin cycle, as demonstrated by you, the students?
I compared the performance of the students who had learned about the Calvin cycle through the standard methods of review with textbook diagrams when I did not use this musical in my classes (a total of 111 students from six classes) to those who had been additionally exposed to this in-class activity (a total of 22 students from one class).