Define water use efficiency, and explain why it is the highest among CAM photosynthesizers.

Under controlled conditions, a transpiration experiment was conducted using two different plant species, A and B. Each plant species was exposed to a low-humidity environment and a high-humidity environment with all other conditions kept the same. The transpiration rate was measured over a period of one hour. The data was graphed as shown below. A B transpiration rate (pl/cm²min) с 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 A bar graph of the transpiration rates of two plants under different humid conditions D 0.04 0.02 low humidity 40% In order to see the effect the change in humidity had on the transpiration rate, what would be a proper con trol to add to the study? high humidity 80% running the same experiment multiple times to collect additional data adding more water to the original plants and running the experiment again grow another set of plants at normal humidity growing more plants at 0% and 100% humidity Species A Species B

Why do the reaction centers have different pigments rather than only the chlorophyls? quantitatively increasing the absorption photons narrowing coverage of the visible spectrum light increasing coverage of the visible spectrum light arranging light-harvesting complexe compensating for the high density of chlorophyll

Explain the expected relationship between the absorption spectra of plant pigments and O2 production, electron transport, and CO2 fixation under various wavelengths of light.