biology lab

1. A.  Briefly, outline the main steps of the photosynthetic pathway.  Be sure to indicate how the light-dependent and light-independent reactions are coupled.

B. Why is Chlorophyll-a central to the light-dependent reactions?  AND – What important role(s) do accessory pigments play in this process?

2. Consider last week’s laboratory exercise concerning carbon-fixation in an aquatic plant.  Recall, we used BTB to monitor pH of the surrounding medium as a proxy for CO2 concentration.    Why might we expect to see a DECREASE in pH in the plant/dark tube?  (i.e., What metabolic process might contribute to this result?)

3.  If a farm pond, stocked with fish and plants, were measured for pH at sunrise and sunset what would be the results?  Why?

4. Describe the redox reaction that was the subject of the “Hill reaction”.  What is normally the final electron acceptor and what did we use as a substitute? Why did we use what we used?