What is photorespiration? How does it differ from dark respiration? What is the cost of photorespiration to the plant? Why does it happen? What conditions lead to higher rates of photorespiration?

How does the C4 pathway solve problems of photorespiration? What is the role of the Calvin cycle in C4 photosynthesis? What is the primary enzyme, the precursors, the products and the cost of the C4 pathway? Is this a cycle? What is Kranz anatomy? Why don’t all plants have C4 photosynthesis? In what regions is C4 particularly important? Why?

How is CAM photosynthesis similar to and different from both C3 and C4? What are the advantages and disadvantages of each?

Reading: pp. 76-81, Chap.31

What are the components of the full water potential equation? How does each affect the free energy and movement of water - between cells, and between plant and soil?

What is transpiration and why is it a "necessary evil"? How important is transpirational water loss in the whole water budget of a plant? Why can’t capillarity and air pressure account for transpirational movement of water through plants? How does water potential and the tension-cohesion mechanism account for this movement? What is the water potential gradient through a plant?

What factors, both biotic and abiotic control rates of transpiration?

What components of water potential account for night-time root pressure in some plants? What is guttation? What is hydraulic lift and how does it work? How does it relate to water potential and water potential gradients? What are some ecological consequences of hydraulic lift?

What moves through phloem? What is meant by "source-sink" relationships in phloem flow? How does phloem flow differ from xylem flow? What is the pressure flow hypothesis and the three main steps involved? How does each step work?

Reading: Chap. 30, pp. 726-731, 736-742

What is an "essential element"? What is the difference between macronutrients and micronutrients? Who are the macronutrients, where do they come from, and what is at least one major function of each?

What two factors contribute to the deficiency symptoms for the different nutrients? Which macronutrients have high, intermediate and low mobility?

Why is nitrogen important to plants? In what forms is N available to plants in soils? What steps are important in plant assimilation of nitrogen and how does this differ among the different available forms?

What are the main steps of the nitrogen cycle? what are the main pools and fluxes? What organisms mediate the different steps? Why is N-fixation important to the nitrogen cycle?

What happens in the process of N-fixation? Who does it? What is the mutualistic tradeoff in symbiotic N-fixation? How specific is this process? What are the steps in nodule formation? What factors potentially constrain N-fixation and how does the plant solve the oxygen problem?

Reading: Chap. 28 to p.693

What is the definition of a hormone? What factors control the expression of a hormone-induced response? What is signal transduction pathway and what is at least one example from the hormones that we studied?

What is the primary natural auxin? Where is it made and how is it transported? What are the effects of auxin and how do they work? What is an experiment that demonstrates the role of auxin in apical dominance? What auxin mimics are important and why?

What are cytokinins, where are they made, and what are their effects? How do they interact with IAA? How were cytokinins discovered and how are they used today? What is totipotency?

What are giberellins, where are they made and what are their functions? How do they interact with the aleurone layer in monocot seeds?

What is unique about ethylene? What is its structure and what are its effects? What is a climacteric fruit and some examples of that type of fruit? How is ethylene used commercially now? How has this use contributed (indirectly) to the downfall of tomato flavor?

How does abscisic acid (ABA) affect stomatal closure?

Reading: chap. 29, pp. 702-714.

What is a positive tropism and what is a negative tropism? How does gravitopism work in roots and shoots? How is the mechanism and response similar and how different in these different tissues? What is phototropism and what is its mechanism of action?

What are the different photoperiod plant types? What role does phytochrome play in photoperiod sensation? What is phytochrome's sensitivity to different wavelengths of light? How does a plant measure the length of a dark cycle? How do we know these things from studies of seed germination and flowering?

What other roles does phytochrome play in etiolation and growth responses in shade? How might these be ecologically important to a plant?