_________________ describes the positive pressure exerted by water on cell membranes. 

Conifers only contain this type of vascular cell__________________. 

_________________ is the process that creates the water potential gradient that drives water movement through the SPAC. 

The following figure shows a light response curve for a forest canopy, a shoot in the forest, and an individual needle on a shoot in the forest. What parts of a light response curve do numbers 1, 2, and 3 indicate? (3 points) Explain why the light response curve for a forest canopy might look so different than that of an individual needle on the shoot. (5 points) Why is photosynthesis negative on this figure? (2 points)

The C4 photosynthetic pathway evolved as an adaptation to minimize photorespiration. What is photorespiration and why does it occur?  (4 points) Explain how the C4 pathway minimizes photorespiration compared to C3 photosynthesis. (3 points) Given this information, how should C3 and C4 plants respond to elevated temperatures? (3 points)

Damage to the proteins of the photosystems by excess light is known as_________________.

The _________________ cells contain Rubsico in C4 plants. 

_________________ is an enzyme that has a dual affinity for CO2 and O2 

The following figure shows the response of stomatal conductance to changing water potential for two different tree species. What is the difference between isohydric and anisohydric stomatal behavior? (4 points) Which data (1-open circles; 2-closed circles) likely represent isohydric and anisohydric species? (2 points) How could plant mortality result from either of these strategies? (4 points)

Air bubbles that form in the xylem under high tensions are known as _____________.